Bradford Factor calculator: score the pattern, see the working.
Third short absence this quarter? Score it in seconds, see exactly how the formula weights frequency over duration — and what a raw score can never tell you.
Score the pattern, with the working shown
36Bradford Factor score — 3 spells, 4 days absent
Most published policies would not act on a score in this range on its own. Trigger levels are employer policy, not law.
The working
- S (separate spells) = 3
- D (total days) = 1 + 2 + 1 = 4
- S² = 3 × 3 = 9
- B = S² × D = 9 × 4 = 36
Why frequency dominates
- One more 1-day spell: score becomes 80 (+44)
- One more day on an existing spell: score becomes 45 (+9)
What the score cannot see
- Absences related to disability, pregnancy or other protected reasons are routinely discounted before scoring — a raw score that includes them can put an employer on the wrong side of the Equality Act 2010. If any spell might qualify, recalculate without it and take advice before acting.
- The score is evidence of a pattern, not a verdict about a person. Trigger levels are employer policy, not law — the bands shown are commonly published examples.
Rules basis: the industry convention B = S² × D over a rolling 52-week window. Not a statutory measure — trigger levels are employer policy, and the bands shown are commonly published examples. Reviewed 28 July 2026 · next review due by 28 July 2027 · Context: Acas absence guidance
The contextA score never manages absence on its own. Acas's absence guidance is the authority on fair process — supportive conversations, adjustments and when a pattern becomes a capability question. ↗What is the Bradford Factor and how is it calculated?
The Bradford Factor scores absence disruption as B = S² × D: the number of separate absence spells, squared, multiplied by the total days absent, usually over a rolling 52-week window. Squaring the spell count is the whole point. Ten single days scores 1,000; one ten-day absence scores 10. Frequent short absences are harder to plan around than one properly managed longer one, and the formula bakes that judgement in.
There is no law behind it. The formula is an industry convention and every trigger level is employer policy — the 50 / 200 / 400 / 600 bands you see published are examples, not rules. Used well, the score points a manager at a pattern worth a supportive conversation. Used badly — scoring disability-related absence, or treating the number as a disciplinary verdict — it creates the tribunal claim it was supposed to prevent.
What matters
Start with the rule
The Bradford Factor scores absence disruption as B = S² × D: the number of separate absence spells, squared, multiplied by the total days absent, usually over a rolling 52-week window. Squaring the spell count is the whole point. Ten single days scores 1,000; one ten-day absence scores 10. Frequent short absences are harder to plan around than one properly managed longer one, and the formula bakes that judgement in.
Write down the decision
Keep the policy, dates, calculation inputs and decision together so another person can understand what happened.
Check the current source
The calculator above shows the arithmetic and the commonly published example bands. Whether a score triggers anything is your policy's call — and any process it starts should follow Acas guidance and the Equality Act 2010.
A practical checklist
For a small team, a short repeatable process beats an impressive policy nobody follows.
- Count each continuous absence as one spell, however long
- Use a rolling 52-week window, not the calendar year
- Discount disability, pregnancy and other protected-reason absences before scoring
- Set trigger levels in your absence policy and apply them consistently
- Treat a trigger as the start of a conversation, not a conclusion
- Pair the score with an absence rate so long-term sickness stays visible
Where software helps — and where it does not
HollyHR can keep the relevant people record, dates, documents, leave and working pattern in one place. It cannot decide a legal, medical or employee-relations question for you.
The calculator above shows the arithmetic and the commonly published example bands. Whether a score triggers anything is your policy's call — and any process it starts should follow Acas guidance and the Equality Act 2010.
Check the source, not just our summary
Rules and product pages change. These are the first-party references behind this page.
Questions people ask
Is this legal advice?
No. It is a practical summary for UK small teams. Check the linked official guidance and take qualified advice for a specific or disputed case.
Why keep the source with the calculation?
Rates and rules change. Recording the inputs, date and source makes the answer reviewable instead of becoming an unexplained number in a spreadsheet.
Can HollyHR track this?
HollyHR can hold the underlying employee, working-pattern, leave and document records. It does not present itself as a legal-advice engine.
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