Skip to content
Small business / Free tool

Overhead allocation calculator

Spread entered overhead across units produced or billable hours in a consistent period.

Your numbersLive result
Choose the question you want to answer.
Display only. No currency conversion.
Required. 0 or more. Use up to 6 decimal places, without commas or currency symbols.
Required. Greater than 0. Whole numbers only. Positive whole units in the same period.

Example values are prefilled. Change any number to calculate.

Overhead per unit

£12.00

Total overhead
£1,200.00
Units
100

Divides overhead evenly across the entered activity for one consistent period. This is a simple allocation assumption; it does not claim every product or hour causes equal overhead. Avoid counting the same overhead twice in pricing.

Your inputs stay in this browser.

The working behind the answer

How to use this calculator

Enter a total for the period and choose the activity across which to spread it. Keep the activity and overhead period aligned. This gives a simple consistent amount that can feed into product pricing or a service-cost model.

The formula

Allocate across units

Overhead per unit = total overhead ÷ units produced

Allocate across billable hours

Overhead per hour = total overhead ÷ billable hours

A worked example

£1,200 of overhead across 100 items allocates £12 per item. Across 200 billable hours it allocates £6 per hour. These are alternative allocation bases, not amounts to add together.

Good to know

Equal allocation is an assumption. Products and hours may use resources differently, so this is not an activity-based accounting system. Do not add the same overhead again elsewhere in a quote or cost model.

Common questions

Can I use decimal hours?

Yes. Unit counts must be whole numbers, but billable hours can be decimal.

What if production volume is zero?

Allocation per unit is undefined, so a positive volume is required.