WIP aging groups unbilled work by elapsed time. Common buckets include 0–7, 8–14, 15–30, 31–60, 61–90, and 90+ days. The right thresholds depend on the firm's actual billing cycle.
Separate Work Date from Entry Date
Preserve both the date work occurred and the date the entry was approved or released. This reveals whether delay came from late timekeeping or from the billing process after approval.
Separate Draft Backlog from Billing Backlog
Draft backlog can signal missing matter, uncertain duration, incomplete narrative, or unresolved classification. Billing backlog can signal prebill delay, billing holds, budget review, or eBilling setup. The owner and fix are different.
Backlog | What to review |
Draft backlog | Matter, duration, narrative, and classification |
Billing backlog | Prebill delay, billing holds, budget review, and eBilling setup |
WIP Aging by Matter
Review total unbilled hours, standard value, oldest entry, average age, draft count, approved count, budget, and billing frequency. A high-value matter with one old entry is different from a matter with dozens of unreviewed days.
WIP Aging by Timekeeper
Repeated late review may appear at the timekeeper level, but the cause may be workload, vacation, poor workflow, matter setup, or integration failure. Use the data for process diagnosis, not simplistic ranking.
Held WIP
WIP may be intentionally held because a milestone has not been reached, settlement is pending, a client requested consolidated billing, or a budget discussion is open. Record the reason, owner, date, and next review date.
WIP and Cash Flow
Long WIP age delays the path from work to invoice. The full cycle is work → time entry → WIP → prebill → invoice → collection. Firms should monitor both realization lockup and collection lockup.
Weekly WIP Review
A weekly review should ask which entries remain in draft, which matters exceed the age target, which prebills await approval, which bills are intentionally held, and which stage owns the next action.
How AI Timekeeping Can Help
AI-assisted capture can reduce the earliest form of WIP delay: work that happened but never became a usable entry. It can surface emails, documents, meetings, calendar events, browser activity, and short tasks for lawyer review.
How MIRA Fits
MIRA helps at the activity-to-entry stage by capturing work, preparing draft entries, and giving users a review workflow inside Microsoft Teams. It can improve the timeliness of the source data feeding WIP, but it does not replace billing schedules or collections.
Related Resources
Authoritative References
This guide is for educational purposes only. Billing, accounting, client, and professional-conduct requirements vary by firm, engagement, and jurisdiction.
Frequently Asked Questions
What is a good WIP aging target?
There is no universal target. It should reflect the firm's billing cadence, client requirements, and fee model.
Should old WIP always be billed immediately?
No. Some WIP is intentionally held. The important control is a documented reason, owner, and review date.
What is the difference between WIP aging and accounts receivable aging?
WIP aging concerns work not yet invoiced. Accounts receivable aging concerns invoices that have been issued but not yet paid.
Can better timekeeping reduce WIP aging?
It can reduce delays caused by missing, late, or incomplete entries, but other billing-stage delays may remain.
