#NULL!Excel error guide No upload

#NULL! in Excel — Invalid range intersection

#NULL! means Excel found a space where it expected a range operator. A space is the intersection operator, so =SUM(A1:A10 B1:B10) is invalid. Replace the space with a comma or use a colon for a continuous range.

Reviewed 31 October 2026 Tested in Excel 365; fixes apply to 2021, 2024 and Mac where the feature exists

The short answer

What it looks like

A SUM or AVERAGE formula returns #NULL!
The formula contains two ranges separated by a space
The error appeared after editing a range reference

Why #NULL! happens

A space between two ranges instead of a comma: =SUM(A1:A10 B1:B10).
A missing colon in a range: =SUM(A1 A10).
A named range that intersects another range with no overlapping cells.
A pasted formula from a locale that uses different separators.

How to fix #NULL!

1
Use a comma to combine ranges
A comma tells Excel to include both ranges. A space asks for their intersection.
```
=SUM(A1:A10,B1:B10)
```
2
Use a colon for a continuous range
If you meant one block of cells, use a colon between the start and end cell.
```
=SUM(A1:A10)
```
3
Replace the formula with a clean one
Delete the formula and retype it with the mouse or keyboard range selection. This avoids invisible separator problems.

A safer formula pattern

=SUM(A1:A10,B1:B10)

Adds both ranges; the comma is required between non-contiguous areas.

Check it in your own workbook

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Related functions

SUM AVERAGE COUNT

Frequently asked questions

What does #NULL! mean in Excel?

How do I fix #NULL! in Excel?

Use a comma to combine ranges: A comma tells Excel to include both ranges. A space asks for their intersection. Use a colon for a continuous range: If you meant one block of cells, use a colon between the start and end cell.

Why does #NULL! appear only in some rows?

Usually because only some rows contain the trigger: A space between two ranges instead of a comma: =SUM(A1:A10 B1:B10). A missing colon in a range: =SUM(A1 A10). A named range that intersects another range with no overlapping cells.

How can I stop #NULL! from appearing again?

Adds both ranges; the comma is required between non-contiguous areas. Use this pattern as a guard: =SUM(A1:A10,B1:B10)

Related Excel error guides

All error codes →

#VALUE!Wrong value type#VALUE! means Excel expected a number, date or logical value but found text, an empty cell or a value from another data type. The fix is to convert the input, remove hidden characters, or guard the calculation with IFERROR.#REF!Broken cell reference#REF! means a formula points to a cell, row, column or sheet that no longer exists. It usually appears after deleting rows or columns, moving a sheet, or pasting a formula into a workbook that does not contain the referenced sheet.#N/ALookup value not found#N/A means a lookup or match function could not find the value. The value may be missing, spelled differently, stored as text instead of a number, or surrounded by spaces. Use exact-match mode and return a clear fallback.#DIV/0!Division by zero#DIV/0! appears when a formula divides by zero or by an empty cell. Excel treats a blank denominator as zero. Check the denominator, exclude blank rows, or return a controlled blank with IFERROR.

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What it looks like

Why #NULL! happens

How to fix #NULL!

Use a comma to combine ranges

Use a colon for a continuous range

Replace the formula with a clean one

A safer formula pattern

Check it in your own workbook

Related functions

Frequently asked questions

Related Excel error guides

Send the workbook and get the formula fixed

What it looks like

Why #NULL! happens

How to fix #NULL!

Use a comma to combine ranges

Use a colon for a continuous range

Replace the formula with a clean one

A safer formula pattern

Check it in your own workbook

Related functions

Frequently asked questions

Related Excel error guides

Send the workbook and get the formula fixed