In Excel: use =FORECAST.LINEAR(x, known_ys, known_xs) — it predicts a single value from a straight-line fit through your historical points.
Syntax
Arguments
| Argument | Description | |
|---|---|---|
x | required | The point to predict a value for. |
known_ys | required | The observed outcomes. |
known_xs | required | The observed inputs, the same size as known_ys. |
Related functions
Select the result cell and type =FORECAST.LINEAR(.
Enter the x value you want a prediction for, then a comma.
Select the known y values, a comma, then the known x values.
Press Enter. Chart the actuals with the prediction to sanity-check the line.
Need it as an auditable file?
Ships inside the linked template — formula-driven, unlocked, audit-ready.
What this does
FORECAST.LINEAR predicts one y for one x by fitting a least-squares line through the known points. It is identical to computing INTERCEPT plus SLOPE times x, just in one call. The newer FORECAST.ETS handles seasonal time series with exponential smoothing and needs a proper date column; the plain linear form assumes a straight-line relationship and nothing more. The legacy FORECAST still works and matches FORECAST.LINEAR. As with any regression, predictions far outside the observed range of x are extrapolation rather than forecasting. The same idea underpins a lot of everyday Excel work, so the few minutes spent getting it right here pay back across every sheet you build afterwards. Treat it as a pattern, not a one-off, and it stops being something you look up and starts being something you reach for. For “cash flow forecast template excel”, the reliable version is a short checking loop, not just the first command that appears to work. Run it on a deliberately small range first, watch how the affected cells change, and only then apply the same setup to the full sheet. When a formula is involved, keep the inputs labelled beside it, reference cells instead of typing values, and apply number formatting only after the result checks out. That is what makes a calculation you can defend to a CFO or an auditor useful in real work: repeatable, auditable, and not dependent on memory or luck.
A worked example
Months 1 to 24 in A2:A25 and revenue in B2:B25: =FORECAST.LINEAR(25, B2:B25, A2:A25) predicts month 25. For a seasonal series with real dates, =FORECAST.ETS(newDate, B2:B25, A2:A25) captures the repeating pattern a straight line cannot. FORECAST puts a defensible projection in a cell instead of a chart annotation, which is what a planning model needs. A practical tip before you scale it up: build it once on a small block of test data, confirm the number against the tool on this page, and only then point it at your real sheet. That one habit catches almost every mistake while it is still cheap to fix, long before a wrong figure reaches a report or a colleague.
In Google Sheets
Everything above works in Google Sheets too. Excel and Sheets share the formula syntax used here; only the surrounding menus are arranged differently. That portability is deliberate — learn it once and it follows you between the two tools and across Windows and Mac. Keep this page bookmarked for the next time the same question comes up. Better still, rebuild the example once in your own sheet — doing it yourself, with the tool above to check against, is what turns a copied formula into a technique you own. Here is the takeaway for “cash flow forecast template excel”: copy the answer if you are busy, but if you have a spare few minutes, rebuild the example in Excel yourself with the tool above open beside it. That single pass — type it, run it, watch the result move when you change an input — is what turns a formula you found into a technique you trust. Keep your inputs labelled and referenced, never hard-coded, and the same sheet stays correct and auditable as it grows. Done that way, you will not need to look this up again, and you will be the person others ask.
Common mistakes
- Predicting far outside the range of the historical x values, where the fitted line carries no evidence.
- Using the linear form on a seasonal series; FORECAST.ETS exists for that and needs evenly spaced dates.
- Mixing up the argument order — the x to predict comes first, then y values, then x values.
Frequently asked questions
What is the difference between FORECAST and TREND?
FORECAST returns one predicted value; TREND returns a whole array of them, and also supports multiple independent variables.
When should I use FORECAST.ETS?
When the data is a time series with a repeating seasonal pattern and evenly spaced dates. The linear form cannot represent seasonality.
Is FORECAST the same as SLOPE plus INTERCEPT?
Yes — =FORECAST.LINEAR(x,ys,xs) equals =INTERCEPT(ys,xs)+SLOPE(ys,xs)*x exactly.
Other ways people ask this
This is also commonly searched as “cash projection template excel”, “excel template cash flow forecast”, “twelve week cash flow forecast spreadsheet excel free” and “twelve week cash flow forecast spreadsheet excel free download”. They describe the identical operation, so you are in the right place no matter how you phrased it.
Why do people search for this in so many different ways?
Because the same task has many names. “cash projection template excel”, “excel template cash flow forecast”, “twelve week cash flow forecast spreadsheet excel free” all point at the one operation explained on this page, which is why they all lead here.