The Real Difference Between Yellow and White Speed Signs in Massachusetts

Is there a difference between yellow and white speed signs in Massachusetts?

Yes.

If you look closely, the black and white signage reads "speed limit" while the yellow does not.

I'm nerdy, and I like to know these things, so I did a little research.

In Massachusetts, and other states as well, there are "Speed Limits" and "Advisory Speed Signs".

The White: Regulatory Speed Limit Signs

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Speed limit signage that includes black legend on a white background indicates the presence of a regulatory limit.

These are speed limits that have a special speed regulation and has been established in accordance with the Massachusetts General Laws and the MassDOT Procedures for Speed Zoning.

The Yellow: Advisory Speeds

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Advisory speed signs have a black legend on a yellow background and are used to supplement other warning signs of a condition that may require a reduction in operating speed, such as an approach to a sharp curve or winding road.

You generally won’t see a yellow advisory speed sign on a straight, open stretch of road with no curves, ramps, or other hazards.

Advisory speeds are not enforceable since their intent is to advise motorists of an appropriate speed, not regulate it. -mass.gov

Within the definition of the yellow sign, my next question was answered. Since it doesn't say "limit", it's not enforceable; however, I wouldn't be seen exceeding the speed by too much that what is displayed in yellow and black.