Switching billers without losing your aged A/R

The decision to change billing companies is usually made over months. The handover is usually planned over days. That asymmetry is where money gets lost, and almost all of it is lost in the same place: the aged accounts receivable left behind with the outgoing biller.

Why the back book gets dropped

Consider the outgoing biller's position. They have been told they are being replaced. Their remaining work is to collect money on which they will shortly stop earning, for a client who is leaving.

Even with goodwill, the back book gets less attention than the live book. The contract rarely says who works claims after the termination date, and so nobody does.

Meanwhile those claims keep ageing toward timely-filing limits, past which they are worth nothing at all.

What to settle before you give notice

Who works the back book, and until when. The single most important clause, and the one most often missing. Either the outgoing biller continues working claims with a date of service before the transition — with their fee continuing on what they collect — or the incoming biller takes it on from day one. Both work. Neither happening is the common outcome.

What you get on exit, and in what format. You want a full A/R ageing report by payer and bucket, the status and notes on every open claim, denial and appeal history, and payer portal credentials where they were created on your behalf. "A CSV of open claims" is not sufficient; the notes are where the context lives.

Who owns the clearinghouse connection. If enrolments were made under the biller's submitter ID rather than yours, re-enrolment can take weeks. Find this out before notice, not after.

Run in parallel. Two weeks of overlap, with the incoming biller working new claims while the outgoing one closes out the back book, costs a little and prevents the gap that otherwise appears exactly at the switch.

Sequence that works

1. Before notice — agree back-book terms in writing. Confirm clearinghouse ownership. Pull a baseline A/R ageing report so you can measure what happens next.
2. Notice — give the contractual period, usually 30 to 90 days. Be straightforward about it. An adversarial exit costs you the back book.
3. Parallel run — new claims to the incoming biller, back book continues with the outgoing one. Both report weekly.
4. Cutover — all new claims to the incoming biller. The back book continues until exhausted or until agreed handover.
5. Thirty days after — compare A/R ageing against the baseline. If the over-90 bucket grew, the back book was dropped and it is still early enough to act.

What to watch during the transition

A dip in collections in the first month is normal and expected — claims in flight take time to land. A dip in the second month is not, and usually means either enrolments are incomplete or the back book stopped being worked.

The baseline report from step one is what makes that distinction visible. Take it before you give notice, not after.