Most household budget spreadsheets die in February. Not because budgeting is hard, but because the sheet was built from a pretty template whose formulas break as soon as you add a row. If you build your own, these five formulas do nearly all the work. They behave the same in Google Sheets, Excel and LibreOffice.
1. SUMIFS: totals by category and month
Keep one long list of transactions (Date, Description, Category, Amount). Then a summary cell like:
=SUMIFS(D:D, C:C, "Groceries", A:A, ">="&DATE(2026,11,1), A:A, "<"&DATE(2026,12,1))
gives November's grocery spend. Change the category or month cell and the summary follows. This is the formula that replaces a separate tab per month.
2. A running balance that survives inserted rows
=SUM($D$2:D2) copied down gives a running total, and keeps working when you insert a row in the middle, which =E1+D2 style chains often don't.
3. Budget vs actual, as a percentage
=IFERROR(actual/budget, 0) and a conditional format that turns the cell amber over 90% and red over 100%. The IFERROR stops a zero budget from filling the sheet with #DIV/0!.
4. Annual costs, spread monthly
Insurance, car tax, subscriptions billed yearly: =annual_amount/12 in a "sinking funds" block, so December's insurance bill doesn't look like a crisis.
5. Days until payday
=payday - TODAY() next to "left to spend" turns a balance into a daily allowance: =left_to_spend / MAX(1, payday - TODAY()).
Keep it honest
- One transactions list, never a list per month.
- Categories in a fixed dropdown (Data validation), so "Groceries" and "groceries " don't split your totals.
- Review once a week, not once a month; it takes five minutes.
If you'd rather not build it
Sheet Reserve has 158 spreadsheet templates with working formulas (budgets, bids, cash flow and engineering calculations) that you can preview before choosing a membership. There's also a one-off Sheet Reserve bundle on Gumroad. If you're still choosing a budgeting app instead of a spreadsheet, listme.name compares software by price model, platforms and limits without needing an account.
Written with the help of an AI assistant for Yunus Emre Vurgun, who makes Sheet Reserve and listme.name.