ISOMITTED Function in Excel: Was an Optional Argument Left Out?

⏱ 1 min readUpdated 28 September 2026

LogicalLevel: ExpertAvailable in: Excel 365 / 2021+

In this article
  1. Syntax
  2. Examples
  3. Example 1
  4. Related functions

ISOMITTED is used inside LAMBDA to give optional parameters default values.

Syntax

=ISOMITTED(argument)
Argument What it means
argument A LAMBDA parameter.

Examples

Example 1

=LAMBDA(amt, [rate], amt * IF(ISOMITTED(rate), 18%, rate))

A GST function that uses 18% unless you pass another rate.

LAMBDA · LET

📚 Part of the free Excel course: Beginner → Expert · Try it in the Formula Lab or ask the AI Helper.

Keep reading

Excel Functions A–ZVAR.P Function in Excel: Variance of a Whole PopulationExcel Functions A–ZFIND Function in Excel: Position of Text (Case-Sensitive)Excel Functions A–ZMUNIT Function in Excel: Identity Matrix
✨ Ask AI about this article

Stuck on a step? Ask a question and the AI answers using this article.

Free · AI can be wrong