Start with comparable money
Do not compare one job using gross salary and the other using take-home pay. For the Work Decisions comparison, use the annual take-home amount you reasonably expect from each role, then keep employer pension value separate. This avoids pretending that a generic tax calculation can represent every person.
Net comparison value = expected take-home pay + employer pension value − recurring work costsRecurring costs can include the part of travel, parking, childcare, uniforms or other work-specific spending that genuinely changes between the roles. Avoid including ordinary household spending that would exist whichever job you choose.
Then count committed time
Paid weekly hours are only part of the time commitment. A role with a long commute or routinely unpaid additional time may consume more of the week than its contract suggests. For a comparison measure, annualise both paid and regular unpaid time using the same number of working weeks.
Committed hours/year = (paid hours/week + regular unpaid/commute hours/week) × working weeksWorked example
Consider two hypothetical roles. The numbers below are illustrative and deliberately exclude tax calculation.
| Input | Job A | Job B |
|---|---|---|
| Expected annual take-home | £31,000 | £34,000 |
| Employer pension value | £2,000 | £2,400 |
| Recurring work/commute costs | £1,200 | £3,000 |
| Paid hours/week | 37.5 | 40 |
| Commute/unpaid time/week | 3 | 7 |
| Working weeks | 47 | 47 |
Job A produces a comparison value of £31,800 after pension and recurring costs. Its committed time is 1,903.5 hours, or about £16.71 per committed hour. Job B produces £33,400 but needs 2,209 committed hours, or about £15.12 per committed hour. Job B still supplies more annual value, but Job A gives more value for each hour committed.
Security, progression, management quality, flexibility, location, health, family needs and enjoyment can outweigh a mathematical difference. The calculation is there to make the trade-off visible.
Questions to check before accepting an offer
- Are the working hours genuinely representative, including regular unpaid time?
- Is bonus income predictable enough to include?
- Have you compared employer pension contributions on the same basis?
- Are travel and childcare costs based on the actual attendance requirement?
- Have you checked probation, notice, leave and contractual terms separately?