SLN Function in Google Sheets: Calculate straight-line depreciation per period

=SLN(cost, salvage, life) requires the initial asset cost, its final salvage value, and its lifetime measured in periods. The result is depreciation for one period. For the ordinary positive-life examples here, the independent calculation is (cost − salvage) / life.

Enter 900 in B2 for cost, 100 in B3 for expected salvage and 4 in B4 for useful life in years. In B5 enter =SLN(B2,B3,B4). Expected depreciation is 200 per year: (900 − 100) / 4.

The model’s year-end carrying amounts are 700, 500, 300 and 100. These follow by subtracting 200 once for each completed year. SLN itself does not know which year a row represents; it returns the same periodic charge for the same three inputs.

If the same 800 depreciable amount is allocated across 48 months, =SLN(900,100,48) gives approximately 16.6666666667 per month. That is one twelfth of 200. Keep the full calculation precision when building a schedule; rounding each of 48 charges to two decimals can leave a residual that a documented accounting policy must address.

For an independent schedule check, put completed years 0 through 4 in A8:A12 and use =$B$2-A8*$B$5 in B8, copied through B12. The expected amounts are 900, 700, 500, 300 and 100. Stop at the chosen life: the arithmetic expression does not automatically stop depreciation at salvage.

• An annual life produces an annual charge; a monthly life produces a monthly charge. Label the units.
• SLN returns a charge, not a final book value or a cumulative charge.
• There is no purchase-date, disposal-date or partial-period argument. A partial-year policy must be modeled separately.
• Use a positive life for this scenario. Exact native error behavior for zero, negative or nonnumeric inputs has not been established.

This is a mathematical allocation example, not a determination of tax deductibility, reporting compliance or an appropriate useful life. Those inputs require the applicable policy. Compare SYD only when a different depreciation pattern is actually intended; changing the function changes the model.

Documented in the rolling Google Sheets service. Documentation reviewed October 19, 2026; an introduction date or numbered release was not established. Examples use English function names, decimal points and comma separators; adapt separators to the sheet’s locale.

The official reference establishes the syntax and function-specific contract. Worked values are original, independently derived expectations, not native Google Sheets observations. No account access, UI screenshot or cross-version execution was performed. Native behavior outside the documented scope remains unverified.