Almost all of the money a practice loses in a billing transition is lost in the handover itself. The outgoing vendor stops working the aging report on a Friday, the incoming one logs in on a Monday, and in between sit unbilled charges, unanswered denials and 835 remittances still routing to a clearinghouse nobody is paying for. The practice absorbs that loss, because the A/R belongs to the practice whether or not anyone is working it.
What this covers
- The practice owns the NPI, the TIN, the payer contracts and the bank account. A billing vendor holds none of them.
- Medicare wants a billing agency change reported on CMS-855B section 8 within 90 days, and the EDI side updated in writing before the change takes effect.
- A billing company’s staff cannot be your authorized or delegated official in PECOS. That role has to come from inside the practice.
- Remittances follow the submitter ID, so changing the clearinghouse means re-routing ERAs payer by payer.
- Reconcile claim counts and posted dollars weekly for the first month. Numbers that will not tie is a transition already leaking.
A billing agency is not enrolled in the Medicare program.CMS Program Integrity Manual, chapter 10, section 10.6.8. It bills in your name and under your number, so the payment keeps your name on it.
None of this is exotic. It is a short list of things that have to happen in a particular order, and the ordering is what practices get wrong. What follows is the file inventory to demand, the Medicare filings and the payer notices, the way to move the aging buckets, and the measurements that prove in the first thirty days that nothing was dropped.
Where A Transition Actually Loses Money
A billing handover fails in a handful of predictable places. The old vendor keeps submitting claims after the agreed stop date, or stops early and says nothing. Denials that were mid-appeal go into a shared drive nobody opens. The Medicare EDI enrollment still names the old clearinghouse, so remittance files keep landing somewhere the practice no longer pays for. Each is a slow leak that surfaces two months later, when the claims are harder to fix.
There is a costlier failure mode. The practice ends the relationship with an aging report and nothing else, then finds it cannot see the claim notes, the payer acknowledgments, the statement history or the appeals in flight. The vendor’s software is a system of record for the vendor. A practice needs one it controls.
Ask it before signing anything new: if we ended this next week, what would we have in hand? The answer has to be a complete patient accounting export plus every open claim and appeal, in a format the practice can open without the vendor’s software.
The Data The Practice Has To Own
Start with the file inventory. Anything the practice cannot pull back is data it will later have to ask permission to see. Ask for machine-readable files, and treat a PDF aging summary as not a deliverable.
- A full patient accounting export: every claim line, charge, payment, adjustment and note, with the dates.
- The open A/R aged by payer and financial class, with claim status and the last action taken.
- Every charge not yet billed, listed by date of service and payer, with the reason it was held.
- Denials and appeals in flight, with the payer deadline, the proof of filing and the appeal level.
- Patient balances, statement history, payment plans and refunds the practice owes.
- Credits, unapplied cash in suspense, and overpayment letters with their response deadlines.
- Payer fee schedules, participation contracts, credentialing records and portal credentials under the practice’s name.
- Payer acceptance and rejection reports, plus twelve months of 835 files and the posting detail behind them.
Two obligations sit underneath that list. The practice, not the vendor, has to keep documentation for seven years and produce it on request from CMS or a contractor (42 CFR 424.516(f)). And the business associate agreement has to cover the ending: at termination the vendor returns or destroys the protected health information it still holds, and where return or destruction is not feasible, the contract’s protections carry over to whatever remains (45 CFR 164.504(e)(2)(ii)(J)).
Read the records clause in the outgoing contract before the final invoice. A vendor that releases data only after payment in full, or only in a proprietary format, has told you what this handover will cost.
What To File With Medicare, And In What Order
Medicare is the payer whose rules are written down and specific, so build the checklist there first and work outward.
| What changed | What to file | Clock |
|---|---|---|
| The billing agency or agent | CMS-855B section 8, Change box with an effective date | Within 90 days |
| Practice location, ownership or an adverse legal action | CMS-855B change of information | Within 30 days |
| The official who signs for the practice | CMS-855B change of information | Within 30 days |
| The bank account receiving payment | CMS-588 EFT Authorization Agreement | With the change request |
| The clearinghouse sending and receiving EDI | The MAC’s EDI enrollment form, such as the CMS-8292 | In writing, before the change |
The details matter more than the form numbers. CMS-855B section 8 lists every billing agency the practice uses, and it states plainly that even with a billing agent, the practice remains responsible for the accuracy of the claims submitted on its behalf. The agency address cannot double as the practice’s correspondence address. Note the clock as well: practice location, ownership and adverse legal action are 30-day reports, and a billing agency change falls in the 90-day bucket for physicians, groups and clinics. DMEPOS suppliers report everything within 30 days.
A delegated official in PECOS must hold an ownership or control interest in the practice or be a W-2 managing employee. Billing company staff cannot take that role for you, and a billing agent is prohibited from signing an EDI authorization on a provider’s behalf. Keep the authorized official and at least one delegated official inside the practice.
One rule removes a category of risk. Medicare pays a billing agent, when it pays one at all, only under an agency agreement with the practice, and payment is always made in the name of the provider or supplier (42 CFR 424.73(b)(3) and 424.80(b)(5)). A transition should never move the payee. If the outgoing vendor’s bank account sits on a CMS-588, fix that first, because a contractor that finds a billing agent’s address in the special payment field can ask for the billing agreement behind it.
The EDI side is a separate filing from enrollment. Under the Medicare Claims Processing Manual, a provider must notify its MAC in writing before it changes a billing agent or clearinghouse, or stops using one (Pub. 100-04, chapter 24, section 50.6). MAC enrollment forms carry separate Vendor Change and ERA Change selections, as the CMS-8292 does: one moves the claims, the other moves the 835 remittances.
Update the EDI enrollment and miss the ERA block, and claims get paid while the explanation of every payment lands at the old clearinghouse. Medicare paper remittances are not a fallback, so the money arrives and the detail does not.
Commercial payers run the same logic through their own processes. Some take an ERA re-route request through the new clearinghouse portal, some want a signed form, and nearly all want notice in writing. Work the payer list one at a time and record the date each request was accepted, because a go-live date means nothing while a payer still has the old clearinghouse on file.
The Moving A/R Plan
Treat the A/R as four buckets. Each one needs a different action, and pretending they are one number is how work gets lost between vendors.
| Bucket | Who works it | What has to happen |
|---|---|---|
| Charges not yet billed | The new vendor, week one | File on a clean claim, dated from the date of service |
| Billed, no determination | Nobody, unless the payer acts | Track the filing, answer any request for information on time |
| Denied or underpaid | The new vendor, with the old notes | Appeal from the original filing date, inside the window |
| Patient and self-pay balances | The practice, with the vendor posting | Statements resume under the practice’s name and policy |
The date of service never changes, and neither does the filing clock. An original Medicare claim has to be filed within one calendar year of the date of service (42 CFR 424.44), and a redetermination request has 120 calendar days from receipt of the notice, with receipt presumed five days after the notice date unless evidence shows otherwise (42 CFR 405.942). Commercial contracts run on their own deadlines, frequently shorter. Sort the unbilled bucket by date of service on day one, oldest first, and you will find the money closest to expiring.
Name the last date the outgoing vendor may submit a claim and the last date it will work a denial. That date belongs in the termination letter, with a copy kept for the payers that ask.
Pull the payer acceptance reports and the 835s covering the week after the stop date. A vendor still billing past cutover is creating duplicates that will be denied or recouped.
Import the A/R file, then reconcile it to the vendor’s closing aging report by bucket and by payer. Any gap gets resolved before the final payment clears.
New claims go out under the practice’s billing provider information, with the new submitter ID registered with each payer through EDI enrollment.
Each open appeal gets a deadline and an owner in the practice’s own tracking, not in the outgoing vendor’s worklist.
Two items deserve their own line. Unapplied cash in a suspense account has to be researched rather than written off, because it is usually a payer waiting on a corrected claim. Refund requests, including Medicare demand letters, carry deadlines that survive the vendor change.
The First Thirty Days: Proving Nothing Was Dropped
Month one is a reconciliation exercise, not a service-level debate. Weekly, pull four numbers from the new system and put them beside the same week from the prior month.
- Claim count by payer: submitted, accepted and rejected, tied to the clearinghouse reports.
- Dollars posted against the expected payments on the ERAs received that week.
- Days in A/R by financial class, measured against the pre-transition baseline.
- Denial inventory count, with the oldest unresolved denial date printed beside it.
- Any payer where claims went out 30 or more days ago and no ERA has arrived.
- The timely filing watchlist: claims whose date of service is nearing the payer’s filing limit.
- Patient statement and refund volume, so nothing quietly parks in a queue.
Some checks will look fine immediately, because payments lag claims by two to six weeks. The ones that fail fast are the rejections and the remittance routes. If a payer rejects claims for an unknown submitter, or the 835s stop for one plan while the rest arrive normally, that payer’s EDI enrollment is incomplete. It fails one payer at a time, so the plan carries a payer list.
This month also shows whether the handover was real. Running those measurements in the practice’s own spreadsheet is what an outsourced medical billing relationship has to support, and a vendor that will not hand over the raw numbers in week one will not hand them over in month six.
Terms That Make The Next Change Easier
Most of the pain in a transition is created months earlier, in a contract nobody kept a copy of. The negotiating window is before the signature, while the vendor still wants the account.
- A transition cooperation clause with dates: export format, delivery deadline, cutover date, and a runout period for the old vendor’s claims.
- A written statement that the practice owns the patient accounting data, the NPI, the TIN, the payer contracts and the portal credentials.
- A business associate agreement that meets 45 CFR 164.504(e), including the return-or-destroy promise at termination and breach notice to the practice.
- A monthly reporting package defined up front: charges, payments, adjustments, A/R by aging bucket, denials by reason and payer, and the clean claim rate.
- A termination clause with notice the practice can live with, and no final-payment hold on the data.
- A named billing agent for Medicare purposes that matches what is filed on CMS-855B section 8.
The reporting list is the part practices skip, and it is what makes a handover manageable, because vendor performance can only be checked against numbers defined in advance. A contract whose only performance figure is a collection percentage gives the practice nothing to measure against.
For the cadence and the reports that should arrive monthly, our medical billing services page lays out how we run an account, and about MedFactor covers who does the work.
Changing medical billing companies: what practices ask
Plan on 45 to 90 days for the full handover. The Medicare change of information and the EDI and ERA enrollments take the longest, and each commercial payer moves on its own timeline. Most practices run both vendors for two to four weeks: the new one starts submitting while the old one finishes the claims and appeals already in flight.
Yes. Report the new billing agency on CMS-855B section 8 using the Change box with an effective date. Physicians, groups and clinics have 90 days from the change, since it falls outside the 30-day items like practice location and ownership. Separately, notify your MAC in writing before the billing agent or clearinghouse on your EDI enrollment changes.
The practice does, at all times. A billing agency is not enrolled in Medicare and bills under the practice’s name and billing number, and payment is made in the provider’s or supplier’s name. Nothing about the vendor relationship changes who is owed the money, which is also why the practice has to be able to produce its own records and file its own appeals.
No. The NPI, the TIN and the Medicare enrollment belong to the practice and stay in place. What changes is the billing agency listed in section 8 and the EDI submitter used to send claims. If the bank account or practice address is also changing, that is a separate report, and a bank change goes on a CMS-588.
They stay valid and keep the original filing date. Watch the payer portals for their status, answer any request for information, and take over the denial and appeal work as the remittances arrive. If the old vendor billed anything after the cutover date, expect duplicates, and release the incorrect submissions rather than appealing them.
The outgoing agreement should require the vendor to return or destroy the protected health information it holds at termination, and to extend the contract’s protections to whatever cannot be returned or destroyed. In practice, ask for the data export in a usable format before the final payment, and keep the old agreement in force until it arrives.
The bottom line
A billing transition is a records project with a filing calendar attached. Get the export in hand, report the change to Medicare and each payer on their own clock, move the aging buckets oldest first, and measure claim counts and posted dollars weekly until the two systems agree. Practices that lose money on a switch lose it in the gap, and the gap is something a practice can plan for.
Getting ready to change billing companies, or already in the middle of it?
Send us your current aging report and the payer list. We will map the unbilled and denied balances by filing deadline, tell you which items will not survive a slow handover, and show you the transition checklist we run with a practice, in the order the filings actually go in.
Request a free A/R transition auditReporting deadlines, EDI enrollment forms and ERA procedures differ by MAC and by payer, and payer policy changes through the year. Confirm the current form and the current filing limit for each payer before you rely on a date in this article; this is billing guidance, not legal advice.
