Accounts Payable Aging: What It Is & How...

It's 7 a.m. on the last day of the month. You pull the AP aging report. The 90+ column shows $14,200 across three vendors. Two called last week saying you're late. One you paid two weeks ago.

That third line is the problem. The payment went out. The remittance email bounced. The vendor's AR system never got it. Your AP aging says open. Their statement says past-due. Both are right from each side. That's what the AP aging report is for: finding these gaps before they become disputes or duplicate payments.

What is accounts payable aging?

Accounts payable aging is a report that lists every open vendor bill and sorts it by how long it's been unpaid. The standard buckets are 0-30 days, 31-60 days, 61-90 days, and 90+ days. Each line shows the vendor name, invoice number, invoice date, due date, and dollar amount. Bookkeepers run it at month-end to manage cash flow, catch stale balances, and verify that payments applied correctly. A healthy AP aging has most of the dollar balance in the 0-30 column. Anything in the 90+ column deserves a closer look.

Key Takeaways

AP aging sorts open bills into four buckets - 0-30, 31-60, 61-90, and 90+ days from the invoice date or due date depending on your aging method
90+ column almost never means the vendor is being ignored - it usually means a payment posted without matching to the bill, a vendor credit sitting unapplied, or a short-pay that was never corrected
Vendor calls that contradict your aging are worth investigating - if you show a bill as paid and the vendor shows it open, the remittance probably didn't reach their AR system
Year-end accrued liabilities are not in AP - bills that arrived in January for December work live in Accrued Liabilities, not AP, until the actual invoice is entered
Clean AP aging takes about 20 minutes monthly - review the 60+ bucket, chase unmatched payments, and apply open vendor credits before the report is final
A heavy 90+ column is a bookkeeping problem, not a cash problem - clean books show errors fast; dirty books hide them until the vendor calls

The AP aging report sits at the intersection of accounts payable workflow and month-end reconciliation. When vendor credit gets miscoded or remittance never reaches the vendor, AP aging is where the discrepancy surfaces first.

What Accounts Payable Aging Actually Is

The AP aging report is a snapshot of every vendor bill entered into your accounting system but not yet fully paid. It's a subledger report, not a P&L report. Expenses already hit the books when bills were entered. Aging tracks whether the liability is still open.

The report organizes bills by time buckets from the invoice date. Standard schedule per the accounting glossary:

0-30 days: Current or just past due. Normal.
31-60 days: Slightly late. May be intentional or a processing delay.
61-90 days: Needs attention. Cash-stretch or a posting error.
90+ days: Almost always a bookkeeping issue, not a vendor relationship issue.

The aging total must match the accounts payable balance on the balance sheet. A $600 discrepancy means something posted to AP via journal entry or a bill was deleted after it was partially paid.

How Bookkeepers Use the AP Aging Report

Month-end AP aging review runs four steps.

Step 1: Run the report and check the total. In QBO, search Reports for "Accounts Payable Aging." Run as of month-end. The grand total should match the AP balance sheet line. If it doesn't, find the gap before touching anything else.

Step 2: Review the 60+ column line by line. Open the vendor's history. Was there a payment that didn't match? A vendor credit sitting unapplied? A payment entered as Expense instead of "Pay Bills," leaving the bill open in AP while cash went out?

Step 3: Compare vendor statements for large 60+ balances. If you show a bill as paid and their statement shows it open, the payment cleared your bank but didn't reach their AR system. Resend proof of payment with the invoice number.

Step 4: Apply open vendor credits. Credits not applied against open bills stay in AP as a negative balance. Apply them before closing the month.

Payments reconciled in the bank feed but not matched to bills in AP are the most common aging discrepancy. The payment reconciliation guide covers the matching workflow.

Common Gotchas at Month-End

Aging buckets that never zero

The most persistent headache: a vendor line that stays open for months even though you keep paying. It's almost always a short-pay or unapplied vendor credit.

Vendor sends a $2,400 invoice. You pay $2,350 due to a damage dispute. QBO marks the bill as partially paid and leaves a $50 open balance. The $50 ages month over month into 90+. Nobody notices. Multiply this across ten vendors and you have $600-900 in AP that never resolves. Fix each: pay the balance, apply a credit, or write it off if the vendor agreed. Don't let short-pays age indefinitely.

When your AP shows paid but the vendor shows open

You ran bill pay, the ACH hit your bank on the 15th, your AP shows $0 for that vendor. The vendor calls on the 22nd asking where their money is.

The payment cleared your bank and matched to the bill in QBO. Your side is clean. Their AR shows open because the remittance never made it to them.

ACH payments carry remittance data in an addenda record. Most bank feeds strip it. The vendor's bank gets the funds but doesn't know which invoice to close. If your remittance email went to a stale contact, the funds sit as unapplied on their side while your AP shows zero.

The fix is documentation, not a second payment. Send bank confirmation with the invoice number in the subject line. Duplicate payments from this gap happen more often than most bookkeepers want to admit.

Year-end accrued vs entered bill timing

December 31st closes. January 8th, a vendor sends an invoice for $6,800 of December consulting work. You enter the bill on January 10th with an invoice date of January 5th. The December expense is missing. The January AP now has a bill for work done in December.

The accrual rule: expenses belong to the period the work was done. Without a bill on December 31st, you can't enter it into AP. The solution is a journal entry on December 31st: debit the expense account, credit Accrued Liabilities. Reverse it January 1st. When the invoice arrives, enter it normally.

What bookkeepers skip: the January 1st reversal. The accrual stays in Accrued Liabilities. The real bill also posts. December gets the expense twice. Set a calendar reminder to reverse every year-end accrual on January 1st.

How Growthy Handles AP Aging

Most AP aging errors start at the categorization step, not the payment step. A bill entered as a direct expense instead of a Bill never hits AP. A payment entered as an Expense instead of through "Pay Bills" leaves the bill open in aging.

Growthy's pattern learning recognizes recurring vendor transactions and flags when a payment route looks different from how that vendor has been handled before. You review and approve. The workflow runs cleaner because the upstream categorization is right more often. For more on the approach to bookkeeping automation, the goal is the same: routine 80% handled automatically, exceptions flagged for your judgment.

FAQ

What is the AP aging report used for?

The AP aging report shows every open vendor bill and how long it's been unpaid. Bookkeepers use it at month-end to manage cash flow, catch posting errors, verify payments applied correctly, and identify vendor disputes before they escalate. Lenders also request AP aging reports during working-capital line reviews.

How do I fix a bill that won't clear from my AP aging?

Open the vendor's transaction history and find the payment. If it posted as an Expense or Check without matching to the bill, apply it to the open bill in QBO via Pay Bills. If there's an unapplied vendor credit, apply it. If the vendor cancelled the bill, book a journal entry: debit AP, credit Other Income.

What's the difference between AP aging and accrued liabilities?

AP aging shows bills entered into the system that remain unpaid. Accrued liabilities cover expenses incurred but not yet invoiced. At year-end, December expenses without invoices live in Accrued Liabilities, not AP, until the actual invoice arrives and gets entered.

How often should I review AP aging?

Monthly, before closing the books. Review the 60+ column line by line. The 90+ column should be clear of anything older than 180 days. Quarterly, verify vendor statements for any balance over $2,000 to catch remittance discrepancies before they grow.

A clean AP aging doesn't mean all bills are paid on time. It means every open balance is there intentionally, and every closed balance actually closed. If the 90+ column grows every month without explanation, the problem isn't cash. It's workflow.

Start with Growthy free and see how it handles recurring vendor categorization so your AP stays cleaner from the start.

Growthy is bookkeeping software, not a CPA firm. This content is educational, not professional advice. Full disclaimer.