The credentialing-to-billing gap, and what each day of it costs.

A provider is hired, credentialed, privileged, and starts seeing patients. Somewhere behind that, a separate process is deciding whether those visits can be billed to anyone. When the two dates diverge — and they always diverge — the visits in between are either billed retroactively, billed under supervision, or not billed at all.

The gap is rarely one big delay. It is an accumulation of small ones, and the useful first step is to stop treating it as a single number.

Three kinds of day, and only two are yours

• Internal days. Assembling the packet, obtaining a signature, discovering a missing attestation. Nobody outside your organization is holding these up.
• Payer days. The plan's own processing time once a complete application is filed. You do not control these, and no software shortens them.
• Silent days. The case that was submitted, acknowledged, and then went quiet because the follow-up lived in someone's memory. On a spreadsheet these look identical to payer days. They are not — they are internal days wearing a disguise, and they are usually the largest single category.

Measuring the three separately is most of the work. A center that reports “enrollment takes about 120 days” usually has 45 internal, 55 payer and 20 silent, and only knows the total.

Why internal days cost more than they look

For Medicare, the effective date of billing privileges is defined by regulation as the later of the filing date of the application that was subsequently approved, or the date the provider first began furnishing services at the enrolled location. The filing date is the pivot.

That means a day spent inside your organization before submission does not merely delay the approval — it moves the effective date forward with it. A retroactive window measured backwards from a later effective date does not recover it. Internal days are therefore not just slower; they are, within the retroactive window, permanently lost in a way payer days are not.

This is a Medicare rule. Puerto Rico Medicaid and commercial plans set effective dates under their own terms, and commercial plans commonly set them at contract execution or credentialing-committee approval with no retroactive window at all. Check the contract in force before assuming any of it carries over. The detail of the Medicare rule is covered in Medicare retroactive billing.

How to measure it without a system

Take the last ten providers you enrolled and, for each, record four dates: start date, packet complete, submitted, effective date confirmed. Four columns, ten rows.

Then compute two intervals: start to submitted (your days) and submitted to effective (mostly theirs). Nearly every center that does this exercise for the first time finds the first interval larger than they expected and highly variable — a range of weeks between the fastest and slowest case, with no obvious reason.

The variance is the finding, not the average. A consistent 40-day internal interval is a process. A range from 12 to 74 days is not a process; it is whatever happened to each provider, and it means the fast cases were fast by luck rather than by design.

What to do with the number

Three things follow directly, and none of them requires buying anything:

• Start earlier. Most of the packet can be assembled before the start date. The constraint is usually that credentialing is notified at hire rather than at offer.
• Make the packet checkable. Most internal delay is a missing item discovered late. A defined per-payer checklist, verified before submission, converts a three-week discovery into a same-day one.
• Put a date on every submitted case. Silent days exist only because nobody owns the follow-up. A next-contact date on every open case eliminates the entire category.

If you want to put a dollar figure on it, the ROI calculator works from your own provider count, payer mix and timeline, and separates what is still recoverable retroactively from what is permanently gone. It shows every assumption so you can disagree with the ones you disagree with.