Detour sign: what it means

Detour sign: an orange diamond with the words DETOUR AHEAD in black
Drawing: Drivoku, based on MUTCD sign W20-2. Simplified; real signs follow the FHWA Standard Highway Signs specifications.

The DETOUR sign warns that traffic will be sent onto a different road or route ahead, usually because of work or a closure.

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What does the DETOUR sign mean?

MUTCD Section 6H.04 says the DETOUR sign should be used before a detour over a different road or route. The distance can be shown as AHEAD or in feet or miles. Detour route markers then guide you along the way.

Quick quiz

What does the sign at the top of this page mean?

  1. Road work ahead.
  2. The work zone ends here.
  3. A detour onto another road ahead.

Show answer

C. A detour onto another road ahead. A detour over a different road or route ahead (MUTCD Section 6H.04). Source: MUTCD 11th Edition, Part 6, Temporary Traffic Control: Sections 6B.09, 6H.04, 6I.02, FHWA; MUTCD 11th Edition, FHWA

Where will you see it?

Before road closures and major work, often with a ROAD CLOSED sign.

What should you do?

Slow down and follow the orange detour signs and arrows until you are back on your route.

What do people get wrong?

Ignoring the detour and trusting GPS directions that do not know about the closure.

Common questions

How do I follow a detour?

Follow the temporary route signs, DETOUR plaques and Detour Arrow signs. MUTCD Section 6I.02 says each detour must be marked with temporary route signs and destination signs.

Is a detour the same as a diversion?

No. In MUTCD terms a detour reroutes traffic onto an existing highway, while a diversion uses a temporary road or alignment around the work area (Section 6B.09).

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Sources

Checked on 3 November 2026 against the MUTCD 11th Edition (FHWA), Sections 6B.09, 6H.04 and 6I.02.

  1. MUTCD 11th Edition, Part 6, Temporary Traffic Control: Sections 6B.09, 6H.04, 6I.02, FHWA
  2. MUTCD 11th Edition, FHWA. FHWA lists the current version as the 11th Edition with Revision 1, dated December 2025

Sign pictures are our own simplified drawings of the MUTCD designs, which are in the public domain (MUTCD Section 1D.06). Sources and image credits.

This text was written with AI help, checked against the MUTCD and approved by Fri Vei AS. Last updated .

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