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South Dakota • Live Time-Zone Reference

South Dakota Time Zone

South Dakota has two time zones. Sioux Falls, Pierre, Aberdeen, Brookings and much of eastern and central South Dakota use Central Time (CT). Rapid City, the Black Hills and much of western South Dakota use Mountain Time (MT).

Quick answer: South Dakota is split between Central and Mountain Time. Fifteen counties are entirely Mountain Time, fifty are entirely Central Time, and Stanley County is divided by the federal boundary. Mountain Time is normally one hour behind Central Time.
Time zones2Central + Mountain
Sioux Falls / PierreCentral TimeCST / CDT
Rapid City / Black HillsMountain TimeMST / MDT
South Dakota Time Zones at a Glance South Dakota Time Zone Map Current Time in South Dakota
Search a South Dakota city, county, related state, time-zone name, abbreviation or UTC offset.
Popular: U.S. Time Zones Central Time Mountain Time Sioux Falls Time Now Rapid City Time Now South Dakota Time Zone Map

South Dakota Time Zone at a Glance

South Dakota's Central–Mountain boundary is a legal geographic line, not simply an east/west midpoint. It follows the Missouri River, an old railway crossing near Pierre, township lines and county boundaries before reaching Nebraska.

CT

Central Time in South Dakota

Sioux Falls, Pierre, Aberdeen, Brookings, Watertown and much of the state use Central Time.

Central Time details → MT

Mountain Time in South Dakota

Rapid City, Spearfish, Deadwood, Sturgis and much of western South Dakota use Mountain Time.

Mountain Time details → DST

South Dakota Daylight Saving Time

Both South Dakota zones currently change clocks in March and November under the U.S. DST schedule.

See DST rules → ⌖

South Dakota Time Zone Map

See the Central–Mountain boundary, split Stanley County and I-90 time-zone context visually.

View South Dakota map → FSD

Current Time in Sioux Falls

Sioux Falls is the clearest live Central Time reference for eastern South Dakota.

See Sioux Falls time now → RAP

Current Time in Rapid City

Rapid City is the clearest live Mountain Time reference for western South Dakota.

See Rapid City time now →

South Dakota Time Zones by Major City

Major cities span both zones. Sioux Falls and Pierre use Central Time; Rapid City, Spearfish, Deadwood and Sturgis use Mountain Time.

Current time across South Dakota →
South Dakota LocationCurrent TimeCurrent AbbreviationCurrent UTC OffsetReference
Sioux Falls · Minnehaha/Lincoln CountiesLive——Sioux Falls time now
Pierre · Hughes CountyLive——State capital reference
Aberdeen · Brown CountyLive——Northeast South Dakota
Brookings · Brookings CountyLive——East-Central South Dakota
Rapid City · Pennington CountyLive——Rapid City time now
Spearfish · Lawrence CountyLive——Black Hills · Mountain Time
Sturgis · Meade CountyLive——Western South Dakota
Fort Pierre · Stanley CountyFederal zone——Official vs local practice
Central Time Zone Mountain Time Zone South Dakota Time Zone Map

South Dakota Time-Zone Guides & Related References

Continue with the two zone families, official related states, live Sioux Falls and Rapid City time, daylight-saving guidance and the dedicated South Dakota map.

All U.S. time zones →
Eastern & central zoneCentral TimeUsed by Sioux Falls, Pierre, Aberdeen, Brookings and much of South Dakota.→ Western zoneMountain TimeUsed by Rapid City, the Black Hills and much of western South Dakota.→ Central standard timeCSTUTC−06:00 during standard time.→ Mountain daylight timeMDTUTC−06:00 while DST is active.→ Official related stateNorth DakotaAnother Central–Mountain state directly north.→ Official related stateNebraskaAnother Central–Mountain state directly south.→ Live statewide timeCurrent Time in South DakotaCentral and Mountain clocks side by side.→ Live Central cityCurrent Time in Sioux FallsLive Central Time clock for eastern South Dakota.→ Live Mountain cityCurrent Time in Rapid CityLive Mountain Time clock for western South Dakota.→ Dedicated state mapSouth Dakota Time Zone MapSee the legal boundary, I-90 context and Stanley County split.→ Zone mapCentral Time Zone MapSee eastern South Dakota in the broader Central region.→ Zone mapMountain Time Zone MapSee western South Dakota in the broader Mountain region.→
Two South Dakota Clocks

Central & Mountain Time in South Dakota Now

Both South Dakota zones currently follow the same U.S. daylight-saving schedule, so Mountain Time South Dakota normally remains one hour behind Central Time South Dakota. Current abbreviations and UTC offsets are calculated from the date.

Central Time CST CDT Mountain Time MST MDT
Sioux Falls · CentralLive timeAmerica/Chicago · current abbreviation and offset
Rapid City · MountainLive timeAmerica/Denver · current abbreviation and offset
UTC ReferenceLive timeCoordinated Universal Time · UTC+00:00
South Dakota Zone Difference1 hourMountain Time is normally one hour behind Central Time.

South Dakota UTC Offsets: Central vs Mountain

South Dakota does not have one statewide UTC offset. The correct offset depends on location and date.

Explore UTC offsets →
South Dakota AreaIANA ZoneCurrent TimeCurrent UTC OffsetSeasonal Rule
Sioux Falls / Southeast South DakotaAmerica/ChicagoLive—CST UTC−06 → CDT UTC−05
Pierre / Hughes CountyAmerica/ChicagoLive—CST UTC−06 → CDT UTC−05
Aberdeen / Northeast South DakotaAmerica/ChicagoLive—CST UTC−06 → CDT UTC−05
Rapid City / Pennington CountyAmerica/DenverLive—MST UTC−07 → MDT UTC−06
Spearfish / Lawrence CountyAmerica/DenverLive—MST UTC−07 → MDT UTC−06
Fort Pierre / Federal ClassificationAmerica/DenverLive—MST UTC−07 → MDT UTC−06

South Dakota Standard Time vs Daylight Time

Both South Dakota time zones currently observe the U.S. daylight-saving schedule, preserving their normal one-hour difference throughout the year.

Daylight Saving Time guide →
South Dakota ZoneStandard TimeStandard OffsetDaylight TimeDaylight Offset
Central Time · eastern/central South DakotaCSTUTC−06:00CDTUTC−05:00
Mountain Time · western South DakotaMSTUTC−07:00MDTUTC−06:00
South Dakota DST Rules When DST Starts When DST Ends DST by State

Compare South Dakota Central & Mountain Time

Compare Sioux Falls with Rapid City, or switch either side to another U.S. or world location. The live comparison uses each location's current civil-time rules.

Live time
Current abbreviation and UTC offset
Live time
Current abbreviation and UTC offset
Open Full Converter Time Zone Difference

How South Dakota Time Zones Work

Six facts explain nearly every South Dakota time-zone question, including the legal county split, Stanley County, the 2003 boundary change, Pierre vs Fort Pierre and current DST policy.

01 · Two Zones

South Dakota Uses Central & Mountain Time

Sioux Falls and Pierre are Central; Rapid City and the Black Hills are Mountain.

02 · Mountain Counties

15 Counties Are Fully Mountain Time

Bennett, Butte, Corson, Custer, Dewey, Fall River, Haakon, Harding, Jackson, Lawrence, Meade, Oglala Lakota, Pennington, Perkins and Ziebach are entirely Mountain.

03 · Split County

Stanley County Crosses the Boundary

The federal line cuts through Stanley County near Pierre before heading southwest toward Jones County.

04 · 2003 Change

Jones, Mellette & Todd Are Central

DOT moved all three counties into Central Time effective October 26, 2003, eliminating older partial or Mountain classifications.

05 · Boundary Rule

Murdo Is a Named Federal Exception

Municipalities on the Central–Mountain line are assigned Mountain Time by federal regulation, except Murdo, which is specifically assigned Central Time.

06 · IANA

Use America/Chicago & America/Denver

Use Chicago for Central South Dakota and Denver for Mountain South Dakota in current and future date-aware calculations.

Which South Dakota Counties Are in Mountain Time?

Fifteen counties are entirely in Mountain Time: Bennett, Butte, Corson, Custer, Dewey, Fall River, Haakon, Harding, Jackson, Lawrence, Meade, Oglala Lakota, Pennington, Perkins and Ziebach. Stanley County is split by the federal Central–Mountain boundary.

The other 50 counties are entirely in Central Time. That includes Jones, Mellette and Todd, which were moved fully into Central Time by the U.S. Department of Transportation effective October 26, 2003. The current boundary follows the Missouri River from North Dakota toward Pierre, leaves the river near the original Chicago & North Western Railway crossing, runs southwest to Jones County, then follows the western boundaries of Jones, Mellette and Todd counties to Nebraska.

15 full Mountain countiesBennett, Butte, Corson, Custer, Dewey, Fall River, Haakon, Harding, Jackson, Lawrence, Meade, Oglala Lakota, Pennington, Perkins and Ziebach.
50 full Central countiesAll remaining counties except Stanley are entirely on the Central side.
Stanley CountyThe federal boundary passes through the county, so exact location matters.
See the South Dakota Time Zone MapMountain Time Zone

Pierre vs Fort Pierre: Legal Zone vs Local Practice

Pierre is Central Time. It lies in Hughes County on the east side of the Missouri River and uses the same CST/CDT clock as Sioux Falls. Fort Pierre is technically Mountain Time under the federal boundary. Federal regulation also says municipalities located on the boundary are in Mountain Standard Time, with Murdo explicitly singled out as the Central Time exception.

Local practice can be more complicated. South Dakota Game, Fish and Parks documented in 2024 that some areas north of Fort Pierre are technically located in Mountain Time but operate on Central Time because of their association with Pierre. Stanley County's 2026 election information, by contrast, publishes Mountain Time for county polling hours. For legal or deadline-sensitive activity, use the governing agency's stated time; for ordinary scheduling near Fort Pierre, confirm the local convention rather than assuming.

Current Time in South Dakota Central Time Zone Mountain Time Zone South Dakota Time Zone Map
Visual Geography

South Dakota Time Zone Map

South Dakota's boundary is especially important around the Missouri River, Pierre/Fort Pierre, Stanley County and the I-90 corridor. It is not a straight north–south line. The dedicated state map is the best visual owner for city-level and highway-level boundary questions.

South Dakota Time Zone Map Central Time Zone Map Mountain Time Zone Map

Looking for the Current Time in South Dakota?

This page explains South Dakota time zones, UTC offsets, abbreviations, the federal boundary and DST. If your main question is what time it is right now, use the statewide current-time page or the dedicated Sioux Falls and Rapid City clocks.

Statewide current timeCurrent Time in South Dakota
Central city current timeCurrent Time in Sioux Falls
Mountain city current timeCurrent Time in Rapid City
Visual boundarySouth Dakota Time Zone Map

Sources & Methodology

CalendarHours uses location-aware, date-aware time-zone logic rather than hardcoding one South Dakota offset. America/Chicago is used for representative current Central Time locations such as Sioux Falls and Pierre; America/Denver is used for representative Mountain Time locations such as Rapid City and Spearfish.

The current legal Central–Mountain boundary is checked against 49 CFR §71.7(b) and (g). U.S. daylight-saving dates are checked against NIST. The 2003 Jones–Mellette–Todd boundary change is checked against the Department of Transportation's final rule. South Dakota's 66-county count is checked against state labor-market information, and recent DST policy against official South Dakota Legislative Research Council records.

IANA — Time Zone Database eCFR — 49 CFR §71.7 Central–Mountain Boundary NIST — Daylight Saving Time Rules U.S. DOT — 2003 Jones, Mellette & Todd Time-Zone Rule South Dakota DLR — 66 Counties South Dakota Legislature — 2025 SB 186 Committee Action

Reviewed August 20, 2026. IANA architecture baseline: tzdb 2026c. Live clocks, current abbreviations and UTC offsets update automatically from supported browser time-zone data.

South Dakota Time Zone FAQ

What time zone is South Dakota in?

South Dakota uses two time zones. Sioux Falls, Pierre, Aberdeen, Brookings and much of eastern and central South Dakota use Central Time, while Rapid City, the Black Hills and much of western South Dakota use Mountain Time.

How many time zones are in South Dakota?

South Dakota has two official time zones: Central Time and Mountain Time.

Which South Dakota counties are in Mountain Time?

Fifteen counties are entirely Mountain Time: Bennett, Butte, Corson, Custer, Dewey, Fall River, Haakon, Harding, Jackson, Lawrence, Meade, Oglala Lakota, Pennington, Perkins and Ziebach. Stanley County is split.

Which South Dakota counties are in Central Time?

Fifty counties are entirely Central Time, including Minnehaha, Hughes, Brown, Brookings, Codington, Jones, Mellette and Todd. Stanley County is split between Central and Mountain Time.

What time zone is Sioux Falls in?

Sioux Falls is in Central Time. For the live clock, see Current Time in Sioux Falls.

What time zone is Rapid City in?

Rapid City is in Mountain Time. For the live clock, see Current Time in Rapid City.

What time zone is Pierre, South Dakota in?

Pierre, the state capital on the east side of the Missouri River, is in Central Time.

Is Fort Pierre in Mountain Time?

Under the federal boundary, Fort Pierre is in Mountain Time. Local and state operational sources also document Central Time use for some schedules tied closely to Pierre, so verify the exact agency or business schedule when timing is critical.

What is South Dakota's UTC offset?

Central South Dakota is UTC−06:00 during CST and UTC−05:00 during CDT. Mountain South Dakota is UTC−07:00 during MST and UTC−06:00 during MDT.

Does South Dakota observe daylight saving time?

Yes. Both zones currently observe DST. In 2026, daylight saving time runs from March 8 at 2:00 a.m. local time to November 1 at 2:00 a.m. local time.

What IANA time zones should I use for South Dakota?

Use America/Chicago for Central South Dakota and America/Denver for Mountain South Dakota.

Is South Dakota ending daylight saving time?

No change is in force as of August 20, 2026. Senate Bill 186 proposed permanent standard time in 2025, but it was deferred to the 41st legislative day and did not replace the current seasonal schedule.