Time-Space Percentage Calculator
Find your IRS time-space percentage and your estimated home-expense deduction — the Publication 587 method, done in about a minute.
Your hours and your home
Results update as you type. Nothing is saved or sent anywhere.
| Hours of care per year | — |
| Total business hours | — |
| Time percentage (÷ 8,760 hrs) | — |
| Space percentage | — |
| Total shared home expenses | — |
| Estimated home-expense deduction | — |
Depreciation of your home itself is calculated separately on Form 8829 using the same percentage.
The time-space percentage decides how much of your shared home expenses — rent or mortgage interest, utilities, insurance, repairs — you can deduct as a home daycare business. This is the IRS method from Publication 587, the same one tax preparers use.
How the time-space percentage works
Time percentage = the hours your home is used for your daycare business during the year, divided by the total hours in a year (8,760, or 8,784 in a leap year). Count the hours children are in care plus hours you spend on business activities when children are not there — cleaning, meal prep, record-keeping, interviewing parents.
Space percentage = the square footage regularly used for the business, divided by your home's total square footage. "Regularly used" means the children are in the room on a weekly basis as part of normal care — it does not have to be used only for daycare. A room used exclusively for the business counts at 100% instead: the calculator handles that by splitting it out of the regular-use area.
A worked example
The IRS's own example in Publication 587: a provider open 12 hours a day, 5 days a week, 50 weeks a year logs 3,000 care hours — a time percentage of 3,000 ÷ 8,760 = 34.25%. If that provider regularly uses 1,000 of a 2,000 sq ft home (space % = 50%), the time-space percentage is 34.25% × 50% = 17.12% — applied to $20,000 of shared home expenses, that is a $3,424 deduction before depreciation.
Rules worth knowing
- You must have applied for, received, or be exempt from a state daycare license or registration to use this method — see your state licensing guide.
- Keep a calendar or log of your hours for at least two months each year to support the time calculation in an audit, and a simple floor sketch or listing for square footage.
- Expenses used 100% for the business (a fence around the play yard, daycare insurance) are deducted in full — do not put them through the percentage.
- Food is deducted separately, either at actual cost or with the IRS standard meal allowance rates.
Time-space percentage questions
What is a good time-space percentage?
Most family child care providers land between 30% and 45% for the combined figure when the home is used heavily, though it varies widely. The biggest levers are hours open per week and how much of the home children genuinely use on a regular basis.
Can I count hours when children are not in my home?
Yes — hours spent cleaning, cooking, planning activities, doing paperwork, and other business tasks in the home when children are absent count toward the time percentage. Track them; estimates written down during the year beat guesses at tax time.
What if a room is used only for daycare?
Space used exclusively and regularly for the business counts at 100% rather than at your time percentage. Enter it in the exclusive-use field above and the calculator applies the blended result.
Does the time-space percentage apply to my food costs?
No. Food for daycare children is deducted separately — your actual food cost, or the IRS standard meal and snack rates ($1.66 breakfast, $3.15 lunch/supper, $0.93 snack for 2025). See the tax deductions guide.
This calculator and guide are general educational information based on IRS Publication 587 — not tax advice for your specific situation. Providers with employees, home purchases or sales during the year, or an S-corp should review their numbers with a tax professional who works with child care businesses.