Written by Muneeb Rana · Last updated 26 October 2026
Quick answer: US speed limits are set by states and local governments, not the federal government. Typical posted limits are about 25–35 mph in residential and urban streets, 45–65 mph on rural highways, and 65–80 mph on many interstates, with the highest posted limits in parts of Texas. Always follow the posted sign; limits vary widely.
TL;DR
- States and cities set limits.
- Urban streets: often 25–35 mph.
- Interstates: often 65–80 mph.
- School and work zones go lower.
- Posted sign always wins.
Who sets US speed limits
Since the repeal of the national maximum speed limit in 1995, states set limits, often with local variation. Wikipedia's article summarises the history and current ranges with references.
Typical ranges
| Road type | Typical posted range |
|---|---|
| Residential | 20–30 mph |
| Urban arterial | 30–45 mph |
| Rural two-lane | 45–65 mph |
| Interstate (rural) | 65–80 mph |
| Highest posted | 85 mph (a Texas toll road) |
Indicative only; check signs.
Special zones
School zones, work zones and some residential areas carry lower limits and often higher fines.
Other countries
Most countries use km/h; the UK uses mph with limits of 30 in built-up areas (20 in Wales), 60 on single carriageways and 70 on motorways for cars. See GOV.UK and mph vs km/h.
Does Speedometer PRO show limits?
No. Speedometer PRO does not show speed limits or alerts. See speed limit app for what to look for.
How limits are set
US states set limits for their own roads. Engineers often consider the 85th percentile speed, the speed at or below which 85% of drivers travel, along with crash history and road design. IIHS research links higher limits to more deaths.
Unposted limits
Many states have statutory limits that apply where no sign is posted, such as in residential districts or school zones. Check your state's DMV handbook.
Highest limits
Parts of Texas have posted limits up to 85 mph, the highest in the US.
Check locally
Limits change; always follow posted signs.
Why limits matter
See dangers of speeding and IIHS research on raising limits.
Related: Speedometer app safety: how to use it without distraction · Speed limit app: what to look for · The dangers of speeding · MPH vs km/h · Speedometer for car: your phone as a second display · Road trip tracker: log every leg · Stopping distance calculator · Phone mount placement: where to put your phone
Get Speedometer PRO on Google Play · Download on the App Store · Set it up before you move; never handle your phone while driving.
Sources
- Speed limits in the United States (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
- Speed (IIHS): iihs.org (accessed 26 October 2026)
- Speeding (NHTSA): nhtsa.gov (accessed 26 October 2026)
- Speed limits (GOV.UK): gov.uk (accessed 26 October 2026)
FAQ
What is the highest speed limit in the US?
Parts of Texas post 85 mph, the highest in the country.
Who sets speed limits in the US?
States and local authorities, within their own laws.
What is the default limit in a US city?
It varies by state and city, but residential streets are often 25 mph.
Are speed limits the same in every state?
No. Interstate limits, for example, range from about 55 to 85 mph by state and section.
Does the app warn me of speed limits?
No. Speedometer PRO shows speed but does not include speed limit data or alerts.