The example Job cost £527 more than estimated. That total alone does not explain the difference. More labour hours, a higher hourly cost, extra material quantity and a changed subcontract package amount contribute in different ways. Start by separating the arithmetic before deciding why it happened.
This worksheet compares estimated and actual construction Job costs on the same scope and unit basis. It calculates quantity and rate effects for each named item and withholds a completed variance when required inputs are missing.
Use actual estimate and recorded-cost evidence in the blank tab. The worked example uses four categories and illustrative figures, not market rates. Its margin comparison concerns that selected cost basis and should not be presented as net business profit.
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One Excel file with a blank comparison, a four-category worked example and instructions. Quantity and rate effects explain the arithmetic difference between estimated and actual costs.
Establish a like-for-like basis
Identify the work covered by the estimate and the actual records. The comparison needs a consistent scope, period and cost basis. A full-job estimate compared with only the receipts entered so far can show an apparent saving that is simply incomplete information.
Keep the estimate reference and relevant agreement available. If accepted changes expanded the work, identify how they are represented before interpreting the variance. A quantity difference may reflect more agreed scope rather than poorer performance.
Use matching units for each row. Hours, days, square metres and a whole package measure different inputs. A unit-rate split only makes sense when estimated and actual quantities refer to the same unit and item.
Review the tax basis consistently. The worksheet calculates no treatment and should not mix amounts on incompatible bases. Establish what the recorded costs and comparison value represent for the actual business and work.
Enter the estimate and actual inputs
On Your variance, enter the category, item and unit, then estimated quantity and rate followed by actual quantity and rate. Use the evidence note to identify sources and any completeness or scope question.
Estimated cost multiplies the first quantity and rate; actual cost multiplies the second pair. Keep unknown inputs blank rather than inserting zero to complete the sheet. A named line with missing required information remains visibly incomplete.
If actual information is only available as a package total, use a clearly defined package basis where appropriate. Do not invent labour hours or material quantities to make the arithmetic look more detailed. The interpretation is limited by what the records support.
Follow the labour variance
The example estimates 40 labour hours at £30, costing £1,200. Actual records use 48 hours at £32, costing £1,536. The difference is £336, but both hours and rate changed.
Quantity effect uses the extra hours at the estimated rate: eight multiplied by £30 gives £240. Rate effect uses actual hours multiplied by the rate difference: 48 multiplied by £2 gives £96. Those effects add to £336.
The split follows a defined calculation convention. It explains the arithmetic without proving why hours or costs changed. Scope, allocation, task conditions and recording quality still need investigation before drawing a conclusion about the work.
Check what the hourly rate contains. If the estimate used an internal rate including an allocation while actual entries use another basis, the apparent rate effect can reflect that mismatch. Review the definitions before treating it as a price increase.
Compare materials, plant and subcontract
Materials are estimated as 18 m² at £28, giving £504, and actual as 20 m² at £30, giving £600. The £96 variance separates into £56 quantity effect and £40 rate effect under the same convention.
Plant changes from three days at £45 to four days at £45. Its £45 difference is entirely a quantity effect in this model. Check the actual charged period rather than assuming a hire day always matches a day the equipment was used.
The bought package changes from one at £650 to one at £700. That produces a £50 rate effect on the package basis. It does not establish which underlying labour or material component changed, nor that the original supplier agreement was amended.
Together the four categories move from £2,489 estimated to £3,016 actual. Quantity effects total £341 and rate effects £186, adding to £527. Keep those figures connected to the rows instead of reporting a total without its basis.
Check incomplete and duplicated records
Try clearing the actual material rate in the worked example before restoring it. The known actual subtotal falls from £3,016 to £2,416, but that is missing information rather than a saving. The completed variance and actual margin stay unavailable until the named row is priced. This small check shows why the subtotal, missing-line count and guarded outputs must be read together.
The known-cost subtotals sum entered numeric lines and can therefore be partial. The incomplete-comparison count and variance guard are there to stop a missing input becoming an apparently finished result. Read the labels together rather than rely on the subtotal alone.
Review time entries and supplier records for duplication. A subcontract package amount may already cover supply included elsewhere, or a material cost may have been recorded through more than one source. The worksheet cannot decide those relationships from amounts alone.
Separate a cost not yet priced from an actual known zero. A free supplied item or unused allowance can have a zero on a defined basis. A missing supplier bill is an uncertainty to record and investigate, not automatically a zero cost.
Choose a completeness review point for the real Job. Some comparisons are useful during delivery, but their figures remain provisional while relevant costs are outstanding. Retain that limit when communicating the result.
Interpret the margin on this basis
The worked tab enters a £3,500 agreed selling value. Against the four selected estimated categories, the remainder is £1,011 and the margin about 28.89%. Actual selected costs leave £484 and a margin about 13.83%.
Those categories exclude other business costs in the example, so the result is not a net-profit calculation. The number describes the relationship between the entered selling value and selected costs. Review which allocations belong in your own comparison.
If the selling agreement changed, establish the appropriate value and cost scope together. Updating only one side can create a ratio that combines different pieces of work. A customer response and a cost entry remain distinct evidence even when related.
Investigate the difference
Choose the largest supported effect and ask what the records say about it. Extra labour hours may reflect expanded scope, an estimate assumption or a task issue. The calculation does not assign blame or settle the explanation.
Check the source and any relevant work notes before changing a future rate or allowance. An entry coded to the wrong Job needs a correction; a consistent estimate gap may need a different pricing assumption. Those are different actions.
Retain the finding and decision alongside the comparison. A later reviewer should be able to see what was investigated and which assumption changed, rather than find a new estimate figure detached from the evidence.
Review one Job on a defined basis
Choose a defined scope with an estimate and recorded-cost inputs. Complete the paired quantities and rates, resolve the missing rows and inspect the quantity and rate effects. Note any limit that prevents a like-for-like interpretation.
Then investigate one material difference before carrying a lesson into future work. The useful review turns a cost total into an explainable comparison, with its remaining uncertainties visible.
Sources and further reading
Review costs beside the actual work
Explore Jobsworth costs and reporting for estimated and recorded costs.
Explore costs and reporting