Why did this CPA engagement go over budget?
To understand an engagement overrun, compare the original scope and staff-hour budget with the recorded work, then trace the difference to the records that explain it. Keep any unexplained time visible until someone can account for it.
Suppose an engagement was planned at 40 staff hours and finished with 56 recorded hours. The 16-hour difference tells you where to begin the review. It does not yet tell you what to change.
Follow the extra 16 hours
This is a fictional teaching example. Its hours and supporting records are invented to show the method, not a SubAI client result or an industry benchmark.
| Explanation | Extra staff hours | Supporting record in this example | Decision to consider |
|---|---|---|---|
| Added scope | 6 | A documented request for another deliverable, with time entries tied to that work | Partner: review how the added work was approved and whether the scope or billing needs a conversation |
| Repeated work after information changed | 5 | A revised source file arrived after work began; the time entries describe updating the affected schedules | Engagement manager: review how changed information reaches the team |
| Review corrections | 3 | Review notes and linked time entries show the corrections made | Reviewer: identify whether the underlying issue calls for a clearer check, instruction or training |
| Not yet explained | 2 | Time entries say "engagement work" and do not establish the activity | Engagement manager: ask for context and keep the cause unresolved |
| Total | 16 | 6 + 5 + 3 + 2 | Reconciles to 56 recorded hours minus 40 planned hours |
Each hour belongs in one row. For example, time spent revising a schedule after new client information arrived must not also be counted as review corrections.
Make sure you are comparing the same work
Before explaining the difference, confirm that the planned and recorded hours cover the same engagement, period and people. Check that time entries are complete enough for the review and that time was charged to the correct work.
Retain the original budget and note any later approved changes separately. Otherwise, a revised budget can obscure when the scope changed and what was originally expected.
Keep elapsed waiting time separate from staff effort. If a file sits untouched for several days, those days do not become staff hours. Time spent checking for it, contacting the client or redoing affected work may be recorded effort.
Start with your practice software
Your existing records may already make the comparison easier. Karbon's help documentation describes work cards and overlays that show budget progress, task information and work status.
Check what your own system records before creating another report. Confirm the access and exports available to your firm. A useful review can combine that information with the agreed scope, change requests, deliverables and review history.
Keep explanations attached to evidence
For each group of extra hours, keep the relevant time entries beside the record that explains them. Label a possible explanation as needing confirmation until the engagement manager or partner accepts it.
In the example, the two hours labeled "engagement work" remain unexplained. Ask what work that entry covers before assigning a cause.
When several people worked on the engagement, review the process and records before drawing conclusions about individual performance. Missing detail in a time entry does not establish that the time was unnecessary.
Choose the change that fits the cause
A review might lead to a clearer scope approval, a way to flag updated client information, an earlier quality check, or more investigation. Some findings will be handled through existing software or a change in the firm's process.
For work that repeatedly requires someone to reconstruct the history, SubAI can explore comparing scope, time records, revisions and deliverables and preparing findings for partner review. Your firm decides what to change in the process, scope or billing.
Assess how much of the 16-hour overrun could be reduced before estimating any benefit from automation. A decision about charging the client needs a review of the engagement's terms and circumstances.
Check the next comparable engagement
Record the change the partner chose, who owns it and when it will be reviewed. On the next engagement with comparable scope, look at whether the same cause recurs.
Useful measures include the hours with a supported explanation, the hours still unexplained, the staff time spent conducting the review and whether the agreed changes were completed. Record corrections to the findings as well.
If the review identifies a recurring manual task, use your own volume, handling time and staff-cost inputs to estimate its current work cost. The calculator can help with that baseline. It does not measure how much of an overrun can be recovered. Staff time freed up after remaining review and corrections is a capacity estimate, separate from a confirmed reduction in spending.
See SubAI's examples for CPA and accounting firms. Bring one engagement where explaining the overrun took too much digging, and we can explore whether there is a useful place to start.