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Part 2 of 7 · Holiday accrual tracker series ~5 min read

What a leave year actually is, and why yours might be 46 of them

A balance is meaningless without a window. Every hour of holiday belongs to a particular twelve months, and almost every argument about holiday turns out, on inspection, to be an argument about which twelve months a particular hour belonged to.

Key takeaways

  • A leave year is whatever the contract says. That is the first place to look.
  • With nothing agreed, it defaults to the anniversary of each worker’s start date.
  • That default gives a business as many year ends as it has workers.
  • The 5.6 weeks is really two pots with different pay and carry-over rules.
  • Record which boundary applies to whom, and where you got it from.

Where the boundary comes from

Three sources for a leave year boundary converging on one entitlement windowThree boxes on the left feed one box on the right. The contract names a leave year explicitly, and the instruction is to read it. A written policy in a handbook, offer letter or signed variation, and the instruction is to read it too. Nobody said, meaning no document names a leave year, in which case the default applies. All three converge on Leave year boundary, holding a start date and where it came from, which feeds a box labelled Entitlement window: the twelve months a balance belongs to. A note says the third lane is the common one and the expensive one, because the default is per-worker rather than per-business.The contractnames a leave yearexplicitlyread itA written policyhandbook, offer letter,or a signed variationread it tooNobody saidno document namesa leave yearthe default appliesLeave year boundarya start date, andwhere it came fromEntitlement windowthe twelve months abalance belongs toThe third lane is the common one and it is the expensive one, because the default is per-worker rather than per-business.
Fig 1. Three routes to one boundary. Which route you took is recorded, because the third one produces a different answer for every member of staff.

The default is per-person, and that is the problem

Where no leave year has been agreed in writing, each worker’s own runs from the anniversary of the day they started. This is a sensible rule — it guarantees everybody gets a full twelve months to use a full year’s entitlement — and it quietly means a business of forty-six people that never wrote anything down has forty-six year ends scattered across the calendar.

Nobody administers that by hand, so what actually happens is that the business invents a single year end, usually the one the accounts run to, and applies it to everybody. That is fine right up until somebody who joined in November leaves in September, at which point the balance they are owed and the balance in the spreadsheet are calculated over two different periods and disagree.

The fix is not clever. It is to record the boundary per worker, along with the document it came from, and to set a proper contractual leave year for new starters so the population of per-person years stops growing. The system can hold both at once, which is what a business in this position actually needs.

The two pots inside one year

The 5.6 week statutory minimum split into a four week pot, a 1.6 week pot and contractual extraA horizontal row of five boxes joined by arrows. Five point six weeks, the statutory minimum. Four weeks, paid at normal remuneration. One point six weeks, paid at basic contractual pay. Anything more, being contractual extra under the employer's own rules. And Different rules, covering pay, carry-over and what survives a year. A note says the layers are paid differently and carry over differently, and a single balance column cannot represent any of that.ONE ENTITLEMENT, THREE LAYERS5.6 weeksthe statutoryminimum4 weekspaid at normalremuneration1.6 weekspaid at basiccontractual payAnything morecontractual extra,employer's own rulesDifferent rulespay, carry-over andwhat survives a yearThe layers are paid differently and carry over differently. A single balance column cannot represent any of that.
Fig 2. The statutory minimum is not one thing. It is two pots with different pay rules stacked on top of each other, plus whatever the employer adds voluntarily.

Why the split is worth carrying in the data

Normal remuneration means what the worker normally earns, which for a lot of irregular-hours staff includes regular overtime, shift premiums and commission. Basic contractual pay means the contractual rate. For a warehouse worker who does six hours of Saturday overtime most weeks, those two numbers are not close, and four weeks of the year are paid at the higher one.

Businesses that pay everything at basic underpay, and businesses that pay everything at normal overpay, and neither of them finds out until an employment tribunal or an accountant does the multiplication. The system carries the split because carrying it costs one field and reconstructing it later costs a year of payslips.

The carry-over rules differ across the same boundary, which part four covers. It is enough here to note that the pots are not interchangeable, and that when leave is taken the system has to decide which pot it came out of. It takes it from the pot that expires first, which is the answer that leaves the worker best off and is therefore the safe default.

What the leave year record holds

  • Start date. The day the window opens for this worker.
  • Source. Contract, policy, or the statutory default.
  • Evidence. A link to the document, not a note that one exists.
  • Entitlement basis. Statutory minimum, or a contractual figure above it.
  • Pot split. How much of the entitlement sits in each layer.
  • Superseded by. Set when a new contract moves the boundary.

Moving a leave year

Businesses do consolidate onto a single leave year, and it is a good idea. The mechanics are the part that goes wrong: the transition produces a short year for most people, that short year still has to carry a proportionate entitlement, and the entitlement already accrued in the part-year cannot be reduced by the change.

So a move is recorded as two windows rather than as an edit to one. The old window closes on the day of the change with whatever it accrued, and a new window opens the next day. The balance carried across is a normal carry-over event with a reason of leave_year_moved, which means the audit trail explains itself without anybody remembering what happened in 2026.

The next post is the arithmetic: how a set of hours in a pay period becomes a number of hours of entitlement, and why that calculation has to run on the hours actually worked rather than the hours somebody was scheduled for.

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