What the Leave Accrual Calculator does
This calculator works out how much paid leave has built up by a given date under an accrual rule you describe: a yearly entitlement credited each pay period, or leave earned per hour worked. It applies a maximum balance, a carry-over limit at the start of each leave year and the leave you have already taken, and lists every credit and deduction so the balance can be checked line by line.
It follows your rule rather than assuming one. Holiday law, employer policies and collective agreements differ widely - UK workers get a statutory 5.6 weeks, many US employers set their own PTO accrual, and some sick-leave laws use a rate per hours worked - so the page shows the arithmetic and leaves the rule to you.
How to use it
- Choose how leave is earned: a fixed yearly entitlement spread over pay periods, or a rate such as 1 hour of leave for every 30 hours worked.
- Pick whether the balance is in days or hours, how often leave is credited, and the date accrual starts - usually the start of employment or of the leave year.
- Enter the date you want the balance for, any opening balance, and limits: the maximum balance (cap) and how much may be carried into a new leave year.
- List leave already taken, one line per absence, as date and amount.
- Read the balance and the schedule. The chart shows where the cap or a carry-over limit stopped the balance growing.
Reading the results
Leave is credited at the end of each pay period, so a balance on a date mid-period does not include that period's share yet. Some employers credit at the start instead; if so, move the start date back one period.
The cap stops accrual; it does not remove leave. While you sit at the cap, each period's credit is lost, which is why the calculator shows how much was not earned.
The carry-over limit is applied on the first day of each new leave year after the start date: anything above it is removed and shown as lost at year end.
Worked example: a first year under a 28-day entitlement
A worker starts on 5 January 2026 with a 28-day yearly entitlement credited monthly - the accrual system UK employers can use in the first year of a job, where a worker gets one-twelfth of their leave each month. Each monthly period ends on the 4th of the following month and adds 28 / 12 = 2.333 days.
By 4 July 2026 six periods have ended: 6 x 2.333 = 14 days. The worker took 3 days on 7 April, so the balance is 14 - 3 = 11 days.
The US example uses 120 hours a year credited every two weeks (4.615 hours a period) with a 40-hour carry-over limit. On 1 January 2026 the balance of about 45.2 hours is cut to 40, and 5.2 hours are shown as lost.
Formulas and scoring rules
- Per pay period
credit = yearly entitlement / periods per yearWeekly 52, every two weeks 26, twice a month 24, monthly 12.- Per hours worked
credit = hours worked in the period / hours per unit x leave per unitHours in a period = weekly hours x 52 / periods per year.- Cap
credit = min(credit, cap - balance), never below 0- Year end
balance = min(balance, carry-over limit) on the first day of each leave year- Balance
opening + credits - leave takenShown to two decimals; the schedule shows three. Nothing is rounded during the calculation.
Accrual in the UK, the US and elsewhere
In the UK almost all workers are entitled to 5.6 weeks' paid holiday a year - 28 days for someone working five days a week - and in the first year of a job an employer can use an accrual system in which the worker gets one-twelfth of it each month. Employers may offer more, and bank holidays can be included in the 5.6 weeks.
The US has no federal requirement for paid vacation, so PTO accrual, caps and carry-over are set by employer policy, with some states and cities requiring paid sick leave - often earned per hours worked. Enter your policy's figures rather than relying on any default.
Limitations: what the result does not prove
- It does not know your legal entitlement. Check the law where you work and your contract; statutory minimums always apply even if a policy says less.
- Rounding rules (for example to the nearest half day) and part-day leave requests vary by employer and are not applied.
- Hourly accrual assumes the same hours every week. For varying hours, run periods separately or use your payroll records.
- It does not calculate holiday pay or payout of unused leave on leaving.
Privacy: where your data goes
Everything you paste, type or drop is processed in this browser tab. It is not uploaded, logged, stored or sent to analytics. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- GOV.UK - Holiday entitlement: accrual and calculation - checked 19 Sep 2026
- US Department of Labor - Vacation leave
Frequently asked questions
How is PTO accrued per pay period?
Divide the yearly entitlement by the number of pay periods. 120 hours a year paid every two weeks is 120 / 26 = 4.615 hours per pay period; 20 days a year paid monthly is 1.667 days a month. The balance grows by that amount each time a period ends.
How much holiday have I built up in my first year in the UK?
If your employer uses the accrual system GOV.UK describes for the first year, you get one-twelfth of your yearly entitlement for each month worked. On a 28-day entitlement that is 2.33 days per complete month, so after six months you have built up 14 days, less any taken.
What happens when my leave balance reaches the cap?
Accrual pauses. You keep what you have, but credits for periods spent at the cap are not added, so that leave is never earned. Taking some leave brings the balance below the cap and accrual starts again.
What does a carry-over limit mean?
It is the most unused leave that can move into the next leave year. On the first day of the new year anything above the limit is removed, unless your policy pays it out or allows an extension. The calculator shows the amount lost.
How is sick leave earned per hours worked calculated?
Divide the hours worked by the accrual ratio. At one hour of leave for every 30 hours worked, 80 hours in a fortnight earns 80 / 30 = 2.67 hours. Choose 'Per hours worked' and enter the ratio and your weekly hours.
Can my leave balance go negative?
Only if your employer allows leave to be taken before it is accrued. The calculator lets the balance fall below zero and flags it, because many employers recover advanced leave from final pay if you leave.
Last reviewed by the A2Z.Tools team against the sources listed above.
