“Our days to payment are terrible. The insurers are slow.”
The second sentence is where the mistake lives.
Here’s the answer: the payer (insurance company) clock doesn’t start until a claim (the bill sent to the insurer) leaves the building. The claim can’t leave until a charge (billable line) exists.
The days before that charge exists belong to the practice, and at most practices nobody counts them.
Charge lag is the count: days from the date a patient was seen to the date the charge was posted in billing. It’s the earliest number in the whole money path that predicts cash, and it’s the one standard reports skip, because every standard report starts at the charge.
The payer clock has not started.
A visit gets marked as kept, and a note gets written and signed (clinical documentation finalized). Then a charge gets created from the signed note, and a claim gets built from the charge and sent.
Charge lag measures the first three of those steps together, in days: it’s the clock on the stretch between the visit and the claim.
Related: note-to-claim gap, appointment status, cash forecast.
What the number looks like when you measure it
At a practice where the signed note creates the charge automatically, charge lag is short. The clinician signs, the charge appears, and the claim can go out the next morning.
At a practice with a charge slip (the paper or screen form that lists what was done) and a weekly billing pass, charge lag stretches. The slips gather in a tray, and on Friday someone keys them in, so a Monday visit waits all week for a charge that takes minutes to create.
At a practice with a signing backlog, charge lag is whatever the backlog is, because a clinician who signs in batches adds days to every visit in that batch.
Don’t invent a target day count from someone else’s practice. Measure your own sample, then decide what “same week” means for you.
Why charge lag predicts cash before anything else can
Every day of charge lag is a day added to the wait for money, and every one of those days is inside the practice’s control.
Take a visit early in the month. If the charge posts the next day, the claim can leave soon, and an insurer that pays on its usual days-to-pay (how long the insurer takes after it has the claim) pays on that schedule. If the charge posts much later, the same insurer pays later. The insurer did nothing different: the practice added days at the source.
The clock most practices measure is the wrong one for that reason. Days to payment blends the practice’s delay with the insurer’s, and blames the insurer for both.
Shortening the wait from a visit to usable cash releases money that had been sitting in transit, and the insurer’s share of the wait doesn’t have to change for it. Charge lag is the front half of the practice-owned wait.
The five numbers that sit on this stretch
Charge lag is one of five measurements that describe the stretch before the claim. A practice that runs all five sees its cash a month before the bank does.
- Charge lag, as days from the visit to the posted charge, by clinician
- Late charges, the share of charges posted more than a few days after the visit
- Unbilled care, the dollars of kept visits that have no charge behind them at all
- Unsent claims, the count and dollars of claims that are complete and still inside the building
- Unsigned notes, the count this morning and the age of the oldest one
The first two are the clock, and the last three are the piles the clock is measuring. A practice with a long charge lag has a big pile somewhere in those three, and the by-clinician view says where.
All five come from records the practice already keeps. The scheduling system knows the visit date, and the billing system knows the posted date. The difference between them, per visit, is the number. No new software collects it, and nobody has asked for it.
Why nobody runs it
Because it isn’t a problem yet: a charge that posts late is still a charge that posts. It will become a claim, the claim will be paid, and the report will show a paid claim. Nothing on that path ever flags the delay.
The days only become visible when they compound into something else. A filing deadline (the insurer’s cutoff for accepting a claim) passes on a visit that waited too long for its charge. A cash shortfall lands in a month when the signing backlog grew. By then the cause is weeks old and looks like something else.
And charge lag is nobody’s number: the clinician doesn’t own the charge, and the biller doesn’t own the note. The owner reads days to payment and calls the insurer slow. The stretch has no owner, so its clock has no reader.
How to pull a clean sample
- Pull last month’s completed visits (or one closed week if last month is huge).
- For each visit, write the visit date and the charge posted date.
- Subtract. That’s charge lag per visit.
- Sort by clinician. Averages hide the person holding the backlog.
- Flag visits with no charge at all. Those aren’t lag. Those are missing charges. Count them separately.
AR aging (unpaid balances by age) and days in A/R (accounts receivable days) won’t show this, because they start after the claim exists.
Real situations that inflate “payer days”
At practices we have worked with, owners blame the insurers for slow payment, and charge lag is the first number worth measuring before that conversation. Once someone measured it, the signing backlog explained most of the wait, while the insurers were paying on contract.
At another, charge lag by clinician ranged from short to long. The practice-wide average looked acceptable, but it hid the clinician holding charges the longest.
At a third, a weekly billing pass that skips the last week of the month for closing leaves those visits waiting for a charge, on a schedule nobody noticed was a schedule.
What shortens lag without creating denials
Two changes, in order.
- Remove the handoff where you can. When the signed note creates the charge in the same minute, with the codes pulled from the note, the middle of the stretch disappears. Charge lag becomes signing lag, and there’s nothing left for a tray to hold.
- Put the signing on a daily number. A short list each morning, by clinician, of what’s unsigned and what it is worth, in the place the clinician already looks. Clinicians will sign what they can see, and they had never seen it.
Then keep the number running. A charge lag that’s measured every morning doesn’t creep back, because the morning it creeps is the morning someone asks why.
Don’t “speed” by under-coding or skipping required fields, because that trades lag for denials (insurer refusals). Short lag with clean charges is the goal.
Why leadership buys the wrong fix
Leadership hears “payers are slow” and opens a contract fight or a collections push.
Both can be right later, but neither fixes days the claim never started.
Measure charge lag first, then argue with payers about the days that remain after your clock ends.
Same-week target, not a hero target
Pick a same-week target your clinic can keep: charge posted inside the same week as the visit for the bulk of visits, with outliers named.
A hero target nobody can hit produces fake posting and real denials, while a same-week target with a standing exception list produces ownership.
What to do with outliers
Outliers teach: a visit with extreme lag usually has an unsigned note, a missing slip, or a provider-setup problem.
Don’t average them away: put them on the exception list with an owner. The average will fall when the outliers get staffed.
What to do this week (simple check)
- Pull one closed week of visits.
- Compute charge lag per visit (visit date to charge posted date).
- Sort by clinician. Name the longest pile.
- Count visits with no charge at all separately.
- Put one owner on the fattest cause (signing, charge entry, or status).
Where this sits on the money path
Appointment status is the first switch, and charge lag is the clock after the visit is known. The note-to-claim gap is the whole map of handoffs. The cash forecast shows which short month a long lag creates if you do nothing.
Charge lag is practice-owned time
Days-to-pay includes the insurer, and charge lag doesn’t.
Until you separate them, every slow bank story will sound like a payer story. Measure your own clock first.
What this means for you
Days to payment tells you how long the money took. Charge lag tells you how much of that was you.
Pull the visit date and the posted date for last month’s charges, subtract, and sort by clinician. The number is on the page in an afternoon, and it will explain a cash problem you have been blaming on someone else.
Grab 30 minutes with us. Prep nothing. You will see your charge lag by clinician for last month, and how many days of cash it is costing you.
Questions people ask
What’s charge lag in a medical practice?
Charge lag is the number of days from the date a patient was seen to the date the charge (the billable line for that visit) posts in billing. It measures the practice’s own delay before a claim (the bill sent to the insurer) can exist. The insurer’s clock hasn’t started yet, so every one of those days is yours to fix.
What’s a good charge lag for a medical practice?
Aim for the charge posted in the same week as the visit for the bulk of visits, with the outliers named. Where the signed note creates the charge automatically, lag is short and the claim can go out the next morning. A paper slip with a weekly billing pass runs longer, and a signing backlog adds whatever the backlog is. Measure your own before copying anyone else’s target.
Why does charge lag matter more than days to payment?
Charge lag matters more because days to payment blends your delay with the insurer’s and blames the insurer for both. Charge lag isolates the days you control, before the claim (the bill to insurance) even exists. Shorten it and every claim leaves earlier, without the insurer changing anything. Measure it first, then talk to insurers about the days that remain.
How do I measure charge lag without new software?
Take the visit date from your schedule and the charge posted date from billing, then subtract for each visit in one closed week or month. Sort the results by clinician, because an average hides the person holding the backlog. Put visits with no charge at all on their own list, because those are missing charges. Both dates already sit in records you keep.
Will posting charges faster create more denials?
Only if you speed up by under-coding or skipping required fields, which trades lag for denials (insurer refusals to pay). The safe way to shorten lag is to have the signed note create the charge, with the codes pulled from the note. Then put unsigned notes on a short daily list by clinician. Short lag with clean charges is the goal.