EDI and EFT Setup for Healthcare Providers: Complete Guide to Electronic Claims and Payments (2026)

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In This Article

• What Are EDI and EFT in Healthcare?
• Why EDI and EFT Matter for Your Practice (Revenue Impact)
• EDI: Electronic Data Interchange Explained
• Common EDI Transaction Types (837, 835, 270/271, 276/277, 834)
• How to Set Up EDI for Claims Submission
• Choosing a Clearinghouse
• EFT: Electronic Funds Transfer Explained
• How to Enroll in EFT with Major Payers
• EDI and EFT Setup Timeline
• Common EDI/EFT Problems and How to Fix Them
• How PayerReady Handles EDI and EFT Setup
• Frequently Asked Questions

Key Takeaways

• EDI (Electronic Data Interchange) handles electronic claims, remittance advice, and eligibility checks between providers and payers. EFT (Electronic Funds Transfer) delivers payments directly to your bank account.
• Practices that submit claims electronically get paid 7-14 days faster than those mailing paper CMS-1500 forms, and EFT eliminates the 3-5 day mail float on reimbursement checks.
• Setting up EDI requires a clearinghouse enrollment, payer-specific trading partner agreements, and correct configuration of your practice management system. Most setups take 2-6 weeks.
• Every major payer now mandates or strongly incentivizes electronic claims submission. Medicare requires EDI for all practices with 10+ employees under HIPAA regulations.
• Common EDI rejections stem from mismatched NPI numbers, incorrect payer IDs, and invalid subscriber information -- all preventable with proper enrollment and testing.

Dr. Sarah Kendrick opened her family medicine practice in Columbus, Ohio, in January 2025. She had her credentialing done, her first patients scheduled, and her billing staff ready. But three weeks in, not a single claim had been paid. The problem was not credentialing delays or denied claims. Her practice had never completed EDI enrollment with her clearinghouse, so every claim she submitted was bouncing back as undeliverable. Meanwhile, the paper checks from two payers that did process her faxed claims sat in a PO Box she checked once a week.

By the time she got EDI and EFT set up properly in March, Dr. Kendrick had $47,000 in delayed revenue and had to take a short-term loan to cover payroll. Her story is not unusual. According to the Council for Affordable Quality Health Care (CAQH), the healthcare industry spent $42.7 billion on administrative transactions in 2024, and providers who still rely on manual processes pay 3-5 times more per transaction than those using fully electronic workflows.

This guide walks you through everything you need to know about EDI and EFT setup -- from transaction types and clearinghouse selection to payer-specific enrollment steps and common problems that delay payments.

What Are EDI and EFT in Healthcare?

EDI (Electronic Data Interchange) is the standardized electronic exchange of business documents between healthcare providers, payers, and clearinghouses. Instead of printing a CMS-1500 claim form and mailing it to Blue Cross Blue Shield, your practice management system sends a structured electronic file (called an 837 transaction) through a clearinghouse to the payer's system. The payer processes it and sends back an electronic remittance advice (835 transaction) showing what was paid, denied, or adjusted.

EFT (Electronic Funds Transfer) is the direct deposit of insurance reimbursements into your practice's bank account. Instead of receiving a paper check in the mail, the payer wires the payment directly. EFT is paired with an Electronic Remittance Advice (ERA) so your billing system can automatically post payments.

Together, EDI and EFT form the backbone of modern healthcare revenue cycle management. They are not optional extras. They are the infrastructure that determines how fast you get paid.

The distinction matters because they are enrolled separately. You can have EDI set up for claims submission but still receive paper checks if you have not enrolled in EFT with each payer. Many practices make this exact mistake -- they get claims flowing electronically but forget that the payment side requires its own enrollment.

Why EDI and EFT Matter for Your Practice (Revenue Impact)

The financial impact of electronic transactions versus paper-based workflows is not marginal. It is transformative.

Speed of payment. Electronic claims reach payers within 24 hours of submission. Paper claims take 5-7 business days by mail, plus time in the payer's mailroom and data entry queue. According to MGMA benchmarking data, practices using full EDI/EFT workflows see an average days-in-accounts-receivable (A/R) of 28-35 days. Practices still mailing paper claims average 45-60 days.

Cost per transaction. The 2024 CAQH Index found that the average cost of a fully electronic claim submission is $0.50, compared to $3.76 for a manual claim. For a practice submitting 500 claims per month, that is the difference between $250 and $1,880 monthly -- a savings of $19,560 per year just on claims submission.

Error reduction. Electronic claims are validated by your clearinghouse before they reach the payer. Formatting errors, missing fields, and invalid codes get caught in the scrubbing process. Paper claims have a first-pass rejection rate of 15-25%, while electronic claims with proper clearinghouse scrubbing achieve 95-98% first-pass acceptance rates.

Payment posting automation. When you receive ERAs (electronic remittance advice) paired with EFT deposits, your billing system can auto-post payments. A full-time billing specialist spends 6-8 hours per week manually posting paper EOBs (Explanation of Benefits). ERA auto-posting eliminates that labor entirely.

Compliance. HIPAA's Administrative Simplification provisions require all covered entities to use standard electronic transactions. If your practice has 10 or more full-time equivalent employees, you are legally required to submit Medicare claims electronically. Even for smaller practices, CMS strongly encourages electronic submission and has been tightening requirements steadily.

EDI: Electronic Data Interchange Explained

EDI in healthcare follows standards maintained by the Accredited Standards Committee (ASC) X12, specifically the X12 5010 version that has been required since January 2012. These standards define exactly how data must be structured in each transaction type.

The EDI ecosystem involves three parties:

1. The provider (your practice) -- generates claims and receives payment information
2. The clearinghouse -- acts as the intermediary, translating your practice management system's output into proper EDI format, validating transactions, and routing them to the correct payer
3. The payer -- receives claims, processes them, and sends back remittance data

Think of a clearinghouse like a postal service that also proofreads your letters before sending them. Your practice management system creates the claim data. The clearinghouse converts it into the correct EDI format, checks it for errors, and delivers it to the right payer. When the payer responds, the clearinghouse translates that response back into a format your system can read.

Some large health systems and billing companies establish direct EDI connections with high-volume payers, bypassing the clearinghouse. This requires significant technical infrastructure and is not practical for most practices.

Common EDI Transaction Types (837, 835, 270/271, 276/277, 834)

Understanding the major transaction types helps you know what you are enrolling for and what to expect from your clearinghouse.

837 -- Health Care Claim

The 837 is the electronic equivalent of the CMS-1500 (professional) or UB-04 (institutional) claim form. There are three variants:

• 837P -- Professional claims (used by physicians, therapists, and most outpatient providers)
• 837I -- Institutional claims (used by hospitals, skilled nursing facilities, and inpatient settings)
• 837D -- Dental claims

The 837P is what most physician practices will use. It contains all the data fields you would find on a paper CMS-1500: patient demographics, subscriber information, diagnosis codes (ICD-10), procedure codes (CPT/HCPCS), dates of service, rendering provider NPI, billing provider NPI, and charges.

835 -- Electronic Remittance Advice (ERA)

The 835 is the electronic version of the Explanation of Benefits (EOB) that payers send with their payments. It details every claim in a payment batch: what was billed, what was allowed, what was paid, what was adjusted, and the reason codes for any denials or reductions.

When paired with EFT, the 835 allows your billing system to auto-post payments to the correct patient accounts. This is the transaction that saves your billing team the most time.

270/271 -- Eligibility Inquiry and Response

The 270 is an eligibility request your practice sends to verify a patient's insurance coverage before their appointment. The 271 is the payer's response confirming or denying coverage details, copay amounts, deductible status, and plan benefits.

Real-time eligibility verification through 270/271 transactions prevents one of the most common revenue cycle failures: rendering services to a patient whose coverage has lapsed or who is seeing an out-of-network provider.

276/277 -- Claim Status Inquiry and Response

The 276 is a claim status request asking a payer where a specific claim stands in processing. The 277 is the response providing the current status -- received, pending, paid, denied, or requesting additional information.

Instead of calling the payer and waiting on hold for 20 minutes to check on a claim, your billing system can send a 276 and get an automated 277 response. This is an underused transaction type that significantly reduces staff phone time.

834 -- Benefit Enrollment and Maintenance

The 834 is used by employers and health plans to enroll members in coverage. Most physician practices will not generate 834 transactions directly, but understanding them helps when troubleshooting eligibility issues. If a patient's 834 enrollment file was not processed correctly, their 271 eligibility response will come back showing no coverage even though the patient insists they are covered.

How to Set Up EDI for Claims Submission

Setting up EDI is a multi-step process that involves your practice management system (PMS), a clearinghouse, and each individual payer. Here is the step-by-step workflow:

Step 1: Verify Your Practice Information

Before anything else, confirm that the following data is accurate and consistent across all systems:

• Billing NPI (Type 2, organizational) and Rendering NPI (Type 1, individual)
• Tax Identification Number (TIN) matching your IRS records exactly
• Taxonomy codes for each provider
• Practice address matching your PECOS and CAQH records
• Payer-specific provider IDs (some payers still assign their own provider numbers in addition to NPI)

A single character mismatch between your NPI registry data and your clearinghouse setup will cause rejections. This is the number one cause of EDI setup failures.

Step 2: Select and Enroll with a Clearinghouse

You need a clearinghouse to act as your EDI intermediary. See the next section for detailed guidance on choosing one. Once selected, the enrollment process typically involves:

• Completing the clearinghouse's provider enrollment form
• Providing your NPI, TIN, and practice details
• Signing a trading partner agreement
• Setting up your user account and login credentials

Step 3: Connect Your Practice Management System

Your PMS or EHR must be configured to communicate with your clearinghouse. This usually involves:

• Entering the clearinghouse's connection details (site ID, login credentials, submission URL)
• Mapping your system's data fields to the clearinghouse's expected format
• Configuring submission settings (batch vs. real-time, auto-submit schedules)

Most modern PMS platforms (Athena, eClinicalWorks, Kareo/Tebra, DrChrono, AdvancedMD) have built-in clearinghouse integrations. If you use a less common system, you may need to set up SFTP file transfers or API connections.

Step 4: Complete Payer-Specific Enrollments

This is where many practices get stuck. Even though your clearinghouse connects to hundreds of payers, each payer must individually authorize your practice to submit claims through that clearinghouse. This is called a trading partner enrollment or payer enrollment.

Your clearinghouse handles most of these enrollments for you, but some payers require additional steps:

• Medicare: Requires separate EDI enrollment through your Medicare Administrative Contractor (MAC). You must submit an EDI enrollment form specific to your MAC.
• Medicaid: Each state Medicaid program has its own EDI enrollment process. Some require enrollment through a designated clearinghouse.
• UnitedHealthcare: Enrolls providers through Optum's provider portal and links to your clearinghouse.
• Anthem/Elevance: Requires enrollment through Availity for most transactions.
• Aetna: Uses the Availity platform for EDI enrollment.
• Cigna: Accepts clearinghouse-initiated enrollments for most transaction types.

Step 5: Submit Test Claims

Before going live, submit test claims (also called companion testing or certification testing) with each payer. Your clearinghouse can facilitate this. Test claims verify that:

• Your data formatting is correct
• The payer recognizes your provider IDs
• Claims route to the correct processing queue
• Remittance data flows back properly

Medicare MACs typically require a formal testing period. Commercial payers generally rely on your clearinghouse's testing process.

Step 6: Go Live and Monitor

Once test claims pass, switch to production mode. Monitor your first two weeks of live claims closely:

• Check your clearinghouse dashboard daily for rejections
• Verify that accepted claims are showing up in payer portals
• Confirm that ERAs are flowing back for paid claims
• Address any new rejection codes immediately

Choosing a Clearinghouse

Your clearinghouse is the most critical vendor in your revenue cycle after your practice management system. The wrong choice creates daily friction. The right choice is invisible -- it just works.

Major Clearinghouses

Availity -- The largest clearinghouse by payer reach, with direct connections to over 2,700 health plans. Availity is owned jointly by Anthem (Elevance Health) and several other major payers. It offers a free portal for eligibility verification and claims status, though full EDI submission services are paid. Many payers now route their provider transactions exclusively through Availity.

Trizetto (Cognizant) -- One of the oldest clearinghouses in the industry, now owned by Cognizant. Trizetto powers the back-end claims processing for many PMS/EHR platforms. If your billing software includes a built-in clearinghouse, there is a good chance it is Trizetto under the hood.

Office Ally -- A cost-effective option popular with smaller practices and billing companies. Office Ally charges no fee for basic 837 claim submission and 835 ERA retrieval, making it an attractive choice for solo practitioners and small groups. The trade-off is fewer advanced features and less robust customer support compared to premium clearinghouses.

Waystar (formerly ZirMed/Navicure) -- A full-service revenue cycle clearinghouse with strong analytics, denial management, and claim status tools. Waystar is popular with mid-size to large practices and billing companies that want more than basic claim routing. Their platform includes predictive denial prevention and automated workflow tools.

Change Healthcare (Optum) -- One of the largest claims processors in the U.S., handling approximately 15 billion healthcare transactions annually. Now part of UnitedHealth Group's Optum division. Change Healthcare powers many clearinghouse integrations behind the scenes.

What to Evaluate

When selecting a clearinghouse, evaluate these factors:

• Payer connectivity: Does the clearinghouse have direct connections with the payers you bill most frequently? Check your top 10 payers specifically.
• PMS integration: Does it integrate natively with your practice management system, or will you need to export/import files manually?
• Rejection reporting: How quickly does the clearinghouse notify you of rejections, and how clear are the error descriptions?
• ERA delivery: Can the clearinghouse deliver 835 files directly into your billing system for auto-posting?
• Cost structure: Per-claim fees, monthly minimums, setup fees, and ERA retrieval fees all vary. A typical range is $0.25-$0.50 per claim for mid-volume practices.
• Customer support: When claims stop flowing at 4:30 PM on a Friday, can you reach a human?

EFT: Electronic Funds Transfer Explained

EFT in healthcare is the direct deposit of insurance reimbursements from the payer into your practice's designated bank account. It replaces paper checks entirely for enrolled payers.

EFT operates through the Automated Clearing House (ACH) network, the same infrastructure that powers payroll direct deposits and online bill payments. When a payer processes your claims and generates a payment, the funds are transmitted electronically to your bank. Simultaneously, the payer sends an ERA (835 transaction) to your clearinghouse so you can match the deposit to specific claims.

The combination of EFT + ERA is where the real efficiency gains happen. Your billing system receives the 835 file, matches it to the bank deposit, and auto-posts payments to individual patient accounts. Without this pairing, you would receive a lump-sum deposit with no way to know which claims it covers without manually reviewing a paper EOB.

CMS EFT/ERA Enrollment

For Medicare, CMS has mandated EFT for all providers through the CMS EFT Authorization Agreement (CMS-588 form). This is separate from your Medicare EDI enrollment. You must submit:

• A completed CMS-588 form
• Your banking information (routing and account number)
• Practice NPI and TIN
• Authorization signature from an authorized signer on the bank account

Medicare EFT enrollments are processed through your MAC and typically activate within 2-4 weeks.

CAQH EnrollHub

For commercial payers, the industry has largely standardized on CAQH EnrollHub (formerly the CAQH EFT Enrollment Tool) as the single point of enrollment. Instead of contacting each commercial payer individually, you enroll once through CAQH EnrollHub, and your EFT/ERA preferences are distributed to participating payers.

Over 150 health plans participate in CAQH EnrollHub, including most major commercial payers. This is a massive time-saver compared to the old process of filling out individual EFT authorization forms for each payer.

How to Enroll in EFT with Major Payers

While CAQH EnrollHub covers many payers, some require direct enrollment or have specific processes.

Medicare

• Form: CMS-588 (Electronic Funds Transfer Authorization Agreement)
• Submit to: Your Medicare Administrative Contractor (MAC)
• Timeline: 2-4 weeks for activation
• Note: Each practice location with a separate NPI/TIN combination needs its own CMS-588

Medicaid

• Process: Varies by state. Most state Medicaid programs have their own EFT enrollment forms on their provider portal.
• Timeline: 2-6 weeks depending on the state
• Note: Some states (Texas, California, New York) have dedicated fiscal intermediaries that handle EFT enrollment

UnitedHealthcare

• Method: CAQH EnrollHub or direct enrollment through Optum Pay portal
• Timeline: 1-3 weeks via EnrollHub, 2-4 weeks via direct enrollment
• Note: Optum Pay offers enhanced remittance detail and early payment options for an additional fee

Anthem / Elevance Health

• Method: CAQH EnrollHub or Availity portal enrollment
• Timeline: 2-3 weeks
• Note: Anthem routes all provider transactions through Availity. If you are not registered on Availity, you should be.

Aetna

• Method: CAQH EnrollHub or direct enrollment through the Aetna provider portal
• Timeline: 2-3 weeks via EnrollHub
• Note: Aetna was acquired by CVS Health and has consolidated many provider processes

Cigna

• Method: CAQH EnrollHub or CignaforHCP.com provider portal
• Timeline: 2-4 weeks
• Note: Cigna merged with Express Scripts and has been updating their provider enrollment systems

Humana

• Method: CAQH EnrollHub or direct enrollment through Availity
• Timeline: 2-3 weeks
• Note: Humana has increasingly moved transactions to the Availity platform

Blue Cross Blue Shield

• Method: Varies by BCBS licensee (each state has a separate BCBS plan). Most participate in CAQH EnrollHub.
• Timeline: 2-4 weeks
• Note: You must enroll with each BCBS plan separately where you see patients. BCBS of Illinois is a different entity than BCBS of Texas.

EDI and EFT Setup Timeline

Here is a realistic timeline for a new practice setting up EDI and EFT from scratch:

Phase	Task	Timeline
Week 1	Verify NPI, TIN, and taxonomy codes are correct in NPPES and all systems	1-2 days
Week 1	Select clearinghouse and complete enrollment paperwork	2-3 days
Week 1-2	Clearinghouse completes payer-specific enrollments	5-15 business days
Week 2	Configure PMS/EHR clearinghouse integration	1-2 days
Week 2-3	Submit test claims and resolve any rejections	3-7 business days
Week 3	Go live with electronic claims submission	1 day
Week 1 (parallel)	Submit CMS-588 for Medicare EFT	2-4 weeks to activate
Week 1 (parallel)	Enroll in CAQH EnrollHub for commercial payer EFT	2-3 weeks to activate
Week 1 (parallel)	Complete state Medicaid EFT enrollment	2-6 weeks to activate
Week 3-4	Verify ERA files flowing back for paid claims	Ongoing
Week 4-6	Confirm EFT deposits active for all enrolled payers	Verify each payer

Total time from start to fully operational EDI + EFT: 4-6 weeks.

The critical takeaway: start your EDI and EFT enrollment the same day you submit your credentialing applications. Do not wait until you are credentialed to begin the EDI/EFT process. The two workflows run in parallel, and you want electronic claims and payments ready on day one when your effective dates activate.

Common EDI/EFT Problems and How to Fix Them

Claim Rejections at the Clearinghouse Level

Problem: Claims are rejected before they even reach the payer. Common rejection codes include "Invalid Payer ID," "Invalid NPI," or "Missing Required Field."

Fix: Check your clearinghouse's payer list and confirm you are using the correct payer ID for the specific plan. Many payers have multiple payer IDs for different products (commercial, Medicare Advantage, Medicaid managed care). Verify your NPI is registered in NPPES and matches your clearinghouse enrollment exactly.

Claim Rejections at the Payer Level

Problem: Claims pass the clearinghouse but are rejected by the payer with reason codes like "Provider Not Found" or "Invalid Subscriber ID."

Fix: This usually means your provider record at the payer does not match what is on the claim. Confirm your credentialing with the payer is complete and active. Verify the subscriber ID, group number, and patient demographics match the payer's enrollment file. Run a 270/271 eligibility check before resubmitting.

ERA Files Not Received

Problem: Claims are processing and getting paid, but you are not receiving electronic remittance advice (835 files) through your clearinghouse.

Fix: ERA enrollment is separate from claims submission enrollment. Contact your clearinghouse and confirm you are enrolled to receive ERAs for each payer. Some payers require you to explicitly opt into ERA delivery through their provider portal or through CAQH EnrollHub.

EFT Deposits Not Appearing

Problem: You enrolled in EFT, but checks are still arriving in the mail.

Fix: EFT enrollment can take 2-6 weeks to activate, and some payers require a full billing cycle before switching. Verify your enrollment status through CAQH EnrollHub or the payer's portal. Confirm your banking information is correct -- a single digit transposition in the routing number will cause the ACH transfer to fail, and the payer will default back to paper check.

Duplicate Claims

Problem: Your clearinghouse shows claims as submitted, but the payer says they were received twice, resulting in duplicate denials.

Fix: This happens when a practice resubmits claims that were accepted but not yet adjudicated, mistaking a slow processing time for a lost claim. Check the claim status through a 276/277 transaction or the payer portal before resubmitting. Most clearinghouses have duplicate detection built in -- make sure it is enabled.

NPI Mismatch Rejections

Problem: The payer rejects claims because the billing NPI or rendering NPI does not match their records.

Fix: This is especially common for practices that use a Type 2 (organizational) NPI for billing and Type 1 (individual) NPI for rendering. Some payers require both, some only accept the individual NPI. Check the payer's specific requirements. Also verify that your NPI is correctly linked to your payer enrollment record -- an NPI that is valid in NPPES but not associated with your enrollment at a specific payer will still be rejected.

How PayerReady Handles EDI and EFT Setup

Getting EDI and EFT set up correctly is one of the most overlooked parts of the credentialing process. Most credentialing companies stop at getting your provider numbers and effective dates. They hand you a "congratulations, you're credentialed" letter and leave you to figure out the electronic claims and payment infrastructure on your own.

PayerReady takes a different approach. Our credentialing and enrollment platform tracks EDI and EFT setup as part of the full enrollment workflow, not as an afterthought. Here is what that means in practice:

• Parallel processing: We initiate EDI and EFT enrollment at the same time as your payer credentialing application, so your electronic infrastructure is ready when your effective date activates. No gap between "credentialed" and "able to bill."
• Payer-specific tracking: Each payer has different EDI and EFT enrollment requirements. Our platform tracks the status of each enrollment individually so nothing falls through the cracks.
• Clearinghouse coordination: We work with your clearinghouse to ensure payer-specific enrollments are submitted correctly the first time. If you need help selecting a clearinghouse, our team provides guidance based on your payer mix and practice management system.
• Status visibility: You can see the real-time status of every EDI and EFT enrollment in your provider dashboard, alongside your credentialing status. No more calling the clearinghouse, the payer, and your billing department separately to piece together where things stand.

If you are launching a new practice or adding payers to your roster, explore how PayerReady streamlines the entire process from initial application through active electronic claims and payments.

Frequently Asked Questions

Is EDI required for all healthcare providers?

HIPAA requires all covered entities with 10 or more full-time equivalent employees to submit Medicare claims electronically. For practices under that threshold, electronic submission is not legally mandated but is strongly encouraged by CMS and virtually all commercial payers. In practice, paper claims are so slow and expensive that almost every practice benefits from EDI regardless of size. As of 2025, over 97% of Medicare claims are submitted electronically.

How much does a clearinghouse cost?

Clearinghouse pricing varies significantly. Office Ally offers free basic claim submission and ERA retrieval, making it a popular choice for cost-conscious practices. Premium clearinghouses like Waystar and Availity typically charge $0.25-$0.50 per claim for mid-volume practices, with monthly minimums of $50-$150. Most clearinghouses also charge setup fees of $100-$500. The right choice depends on your claim volume, payer mix, and how much automation and analytics you need beyond basic claim routing.

Can I use different clearinghouses for different payers?

Technically, yes. Some practices use one clearinghouse for commercial claims and another for Medicare or Medicaid. However, this adds complexity to your workflow and splits your reporting. Most practices benefit from consolidating with a single clearinghouse that has strong connectivity with all their major payers. The exception is state Medicaid programs that mandate a specific clearinghouse or direct submission portal.

What happens if my EFT enrollment is rejected?

The most common reason for EFT rejection is a mismatch between the practice name on the enrollment form and the name on the bank account. The TIN on the enrollment must match the TIN associated with the bank account. If rejected, correct the discrepancy and resubmit. CAQH EnrollHub will show the specific reason for rejection in your enrollment dashboard. For Medicare EFT rejections, contact your MAC directly.

Do I need separate EDI and EFT enrollment for each practice location?

If each location has its own NPI and TIN, then yes -- each location needs separate EDI and EFT enrollment. If multiple locations bill under the same organizational NPI and TIN, a single enrollment covers all locations. The key factor is the NPI/TIN combination, not the physical address. This is an important consideration for multi-location practices and organizations managing multiple providers.

How long does it take to switch clearinghouses?

Switching clearinghouses typically takes 2-4 weeks. The new clearinghouse must complete payer enrollments, you must reconfigure your PMS integration, and you need to verify that claims and ERAs flow correctly with the new setup. Plan for a 1-2 week overlap period where you run both clearinghouses simultaneously to ensure no claims are lost in the transition. Notify your payers of the clearinghouse change, as some payers require updated trading partner information.