Diagnostic reference

Unterminated string literal

Why a string fails to close: a missing quote, a newline inside quotes, or smart quotes pasted from a document.

Updated September 12, 2026

Apps Script error

SyntaxError: Unterminated string literal

What it means

A string was opened and never closed on the same line: a missing quote, a newline inside a quoted string, or a smart quote pasted from a document. Use a template literal for multiline text or an escaped newline inside a quoted string. Non-ASCII quotes are not string delimiters and can produce a different syntax error.

Related error messages

SyntaxError: Invalid or unexpected token
SyntaxError: string literal contains an unescaped line break

Before and after

See the change before you make it.

Problem

function greet() {
  const msg = "Hello, world;
  Logger.log(msg);
}

Safer version

function greet() {
  const msg = "Hello, world";
  Logger.log(msg);
}

How to fix it

Close the string with the same straight quote that opened it.
Use a template literal or an escaped newline when the text needs a line break.
Check pasted text for smart quotes, which are not JavaScript string delimiters.

What stays with you

Check text copied from documents for other smart characters.
myFunction does not change string contents beyond the quotes.