605 area code
Sioux Falls area, Central and Mountain Time.Area code 605 covers Sioux Falls, Rapid City, Aberdeen and 266 more places in South Dakota, on Central and Mountain Time.
Right now in South Dakota
Central Time (CST, UTC-6; CDT, UTC-5 in summer) · Mountain Time (MST, UTC-7; MDT, UTC-6 in summer)
Calling hours: Mon to Sat, 9 AM to 9 PM · Sun, no calls (South Dakota law)
Small talk
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Where 605 numbers come from
Numbers are issued by rate center, a billing area named for its main town. 605 has 269. Each one's share is how many 605 numbers start there.
- Sioux Falls12%
- Rapid City7%
- Aberdeen3%
- Spearfish3%
- Watertown2%
- Huron2%
- Pierre2%
Also: Yankton, Mitchell, Brookings, Harrisburg Tea, North Sioux City, Vermillion, Flandreau, Sturgis, Madison, Martin, Milbank, Redfield + 250 more
Share of exchanges (blocks of 10,000 numbers). Source: NANPA rate center and exchange reports, November 10, 2026
When can you call a 605 number?
Sales calls to homes and cell phones have legal hours, set by South Dakota law. Hold every 605 number to them, since you can't tell a work line from a personal cell.
What applies to 605Mon to Sat, 9 AM to 9 PM · Sun, no calls
- Federal (TCPA and FTC rule)Every day, 8 AM to 9 PMCalls to residential and mobile numbers. Most calls to businesses are exempt from the FTC's rule.47 CFR 64.1200(c)(1); 16 CFR 310.4(c) (opens in a new tab)
- South Dakota lawMon to Sat, 9 AM to 9 PM · Sun, no callsCalls to residences.SDCL 37-30A-3(2) (opens in a new tab)
Local time comes from the area code, not from where the person is today. Mobiles keep their number when they move. Calling hours here are a guide, not legal advice. Every state's calling hours, with sources
The 605 area code
605 is one of the original area codes from 1947. Local calls take all 10 digits.
- 1947605 starts
Source: NANPA area code database
Calling a list of 605 numbers?
Paste it into the free phone number validator. It checks every number, finds each one's time zone and sorts the list by who you can call right now.
605 area code FAQ
What area code is 605?
605 is a South Dakota area code for Sioux Falls, Rapid City, Aberdeen, Spearfish and 265 more places.
What time zone is the 605 area code in?
It spans two: Central Time (CST, UTC-6; CDT, UTC-5 in summer) and Mountain Time (MST, UTC-7; MDT, UTC-6 in summer). A 605 number can be on either clock.
What are the calling hours for 605 numbers?
Mon to Sat, 9 AM to 9 PM · Sun, no calls, local time, under South Dakota law.
When did the 605 area code start?
In 1947: it's one of the original area codes.
Calling 605 numbers? Reach more of them.
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