Hybrid Proration Calculator
☆You work from home 3 days and the office 2 — so what share of rent, internet and electricity is business? Apply home-day share × office-area share, and if you moved mid-year, get the month × area × use triple-weighted table. Plus a copy-ready HR hybrid-arrangement letter.
Your inputs are saved on this device
Advanced ▾ (mid-year move)
Prorated deduction base
Home-day share—
WFH days ÷ total days. This is the first weight.
Area share—
Office sq ft ÷ home sq ft. The second weight.
Annual deduction base—
Annual home cost × home-day share × area share. May be eligible as your Schedule C base — confirm with a CPA.
Month × area × use table
No mid-year move: the single-weight result above applies all year.
TurboTax allows at most two home office locations per Schedule C — community threads describe splitting two locations by time (e.g. 75%/25%). A third space cannot be entered as a separate office.
HR hybrid-arrangement letter — copy to use
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Why this matters
The Intuit community thread that asked this question drew more than 10,000 views: as a hybrid worker, what share of my home expenses is business? The answer is two weights, not one. First, the share of days actually worked from home — 3 of 5 days means 60% of home costs are potentially work-related, not 100%. Second, the office's share of the home — a 120 sq ft room in a 1,200 sq ft apartment is 10%. Multiply annual home cost by day share and by area share, and you have the prorated deduction base. Mid-year movers get a third weight: the month. Community threads describe people who moved between two homes splitting the year by time — commonly a 75%/25% split for a September move — and TurboTax, per those threads, accepts at most two home office locations per Schedule C. This tool builds the month × area × use table so the split is defensible rather than estimated.
How it works
Set your WFH and office days per week, the home area, and the current office area plus monthly rent/mortgage. The tool multiplies annual home cost by home-day share by area share. If you moved mid-year, pick the move month and open Advanced to enter the previous home's office area and rent; the result becomes a 12-row table — one row per month, weighted by that location's area share and the day share. The HR letter below is pre-filled with your day split; it exists so your hybrid arrangement is confirmed in writing, which matters if anyone ever questions what days were actually worked from home.
What the results mean
The "annual deduction base" is the figure you may be eligible to enter on Schedule C using either method — it is not a tax guarantee, and a CPA confirms it against current IRS guidance. Keep the correspondence tidy: 12 months of utility bills, the lease, and this table. For the W-2 reader: remember this prorated path is for self-employed workers; as a W-2 employee the same numbers support a reimbursement conversation with your employer instead. Export the table as text to paste into a spreadsheet or share with your preparer.
Frequently Asked Questions
How do I prorate home office for a hybrid schedule?
Apply two weights: the share of days worked from home (3 of 5 days = 60%) and the office's share of the home (office sq ft ÷ total home sq ft). Annual home cost × day share × area share gives the prorated deduction base.
What if I move mid-year?
Split the year by location: months in the old home office use the old area and rent, months in the new use the new ones. Community threads describe a roughly 75%/25% time split for two locations — this tool builds the month × area × use table for you.
How many home offices can I claim?
TurboTax allows at most two home office locations per Schedule C. A third space cannot be entered as a separate office — check with a CPA before filing, and keep both locations' paper trails.