How to Subtract in Google Sheets

Open the sheet named Budget Subtraction. The example occupies Budget Subtraction!A1:D5:

These amounts are synthetic and use one consistent currency.

If necessary, replace the category names in A2:A4. Then enter the planned amounts in B2:B4 and actual spending in C2:C4.

Enter amounts in columns B and C. Column D calculates each difference with a subtraction formula.

Select Budget Subtraction!D2 and enter:

=B2-C2

After you press Enter, Google Sheets performs this calculation:

1200 - 1200 = 0

Next, copy D2 down through D4 by dragging the fill handle or by copying and pasting the cell. Because the formula uses relative cell references, the row numbers adjust automatically:

D2: =B2-C2
D3: =B3-C3
D4: =B4-C4

You should see results of 0, 160, and 85.

Now calculate the totals with:

B5: =SUM(B2:B4)
C5: =SUM(C2:C4)
D5: =B5-C5

The expected total is:

1880 - 1635 = 245

Adding the row-level differences produces the same result:

0 + 160 + 85 = 245

A recorded spreadsheet execution produced these results on 2026-10-17. Two additional checks were also recorded, with each one starting from the original baseline:

• Changing C3 from 340 to 425 produced D3=75, C5=1720, and D5=160.
• Resetting the baseline, then setting B4=0 and C4=0, produced D4=0, B5=1700, C5=1540, and D5=160.

Separately, an anonymous read of Budget Subtraction!A1:D5 displayed the five rows shown above. This readback confirms the displayed data, but it isn’t a new formula calculation.

Since the formula subtracts spending from the budget:

• A positive result means money remains.
• Zero means the budget and spending are equal.
• A negative result means spending exceeded the budget.

For example, if you set B3 to 500 and C3 to 525, =B3-C3 should return -25. This is a suggested manual check rather than one of the recorded execution cases.

If the result looks wrong, check for these common mistakes:

• Reversed references: =C3-B3 produces the opposite sign from =B3-C3.
• Missing equals sign: Entering B2-C2 without = records text instead of starting a formula.
• Nonnumeric inputs: When a referenced cell contains text such as pending, correct the input instead of silently converting it with IFERROR or N.
• Blank inputs: Decide whether a blank represents zero or missing data, then test that policy in a copy of the sheet. Blank inputs weren’t covered by the recorded cases.
• Numbers stored as text: Remove leading apostrophes or other characters, then re-enter the value as a number.

You don’t need to worry about comma-versus-semicolon function separators for =B2-C2 because the formula has no function arguments.

ModelMonkey can inspect the active Google Sheets context and help with formula tasks. For this example, you could submit the following request:

Inspect Budget Subtraction!B2:D5. Check that each Remaining cell subtracts Spent from Budgeted on the same row and that D5 equals B5-C5. Show any proposed formula changes for review.

When the workflow presents a preview, review the proposed changes before proceeding. You should also confirm the results against the expected values because formula suggestions may be incorrect.