Signaled vs. Signalled
Cambridge marks the verb with -ll- in UK usage and usually -l- in US usage, yielding forms such as signalled/signalling and signaled/signaling. This guide treats the pair as a documented spelling or inflection convention rather than inventing a meaning difference where none is supported.
Use “signaled” in ordinary US English and “signalled” in ordinary UK English. Keep the regional spelling consistent.
Key details
Choose the right form
| Meaning / situation | Form / construction | Decision |
|---|---|---|
| ordinary US spelling of the past tense/participle | signaled | Use the single-l spelling in US English. |
| ordinary UK spelling | signalled | Use the double-l spelling in UK English. |
| a publication or organization with a fixed house style | follow that style consistently | Regional convention can be overridden by an explicit style requirement. |
Quick tests
Meaning / construction test
Are you following ordinary UK spelling?
If yes: Use “signalled.”
If no: Use “signaled” in ordinary US spelling, unless house style says otherwise.
Caveat: This is a regional spelling distinction, not a difference in meaning.
Examples
The driver signaled before changing lanes.
“Signaled” follows ordinary US spelling.
The driver signalled before changing lanes.
“Signalled” follows ordinary UK spelling.
The light signaled that the system was ready.
The single-l form is standard in US spelling.
Further guidance
Core difference
Use “signaled” in ordinary US English and “signalled” in ordinary UK English. Keep the regional spelling consistent.
Style Boundary
Choose the form that matches the documented regional or lexical convention, and keep the spelling consistent while preserving official names and quoted text.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Signal — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Cambridge marks the verb with -ll- in UK usage and usually -l- in US usage, yielding forms such as signalled/signalling and signaled/signaling.