Area code 636: Missouri
Area code 636 is a US state area code for Missouri, on Central Time. It has 430 prefixes in service across 46 rate centers, the largest being Saint Charles, Chesterfield and Harvester. NANPA lists no overlay code for it. Local calls there take 7 digits.
Local time in area code 636
America/Chicago
Prefixes in service
430 of 792 possible
46 rate centers
Area code 636 facts
| Location | Missouri, United States |
|---|---|
| Time zone | Central Time |
| Overlays | None |
| Split from | 314 |
| In service since | May 22, 1999 |
| Local calls | 7 digits; toll calls 1 + 10 digits |
| Carrier | Not shown. An area code is where a number was issued; numbers port between carriers. Check line type |
Which cities and towns use area code 636?
NANPA records each prefix against a rate center, the local billing area a number belongs to, usually named after its main town. These are the 636 rate centers with the most prefixes in service. 34 smaller ones aren't listed.
| Rate center | Prefixes |
|---|---|
| Saint Charles | 43 |
| Chesterfield | 35 |
| Harvester | 35 |
| Manchester | 27 |
| O'Fallon | 23 |
| Fenton | 16 |
| Festus Crystal City | 16 |
| Saint Peters | 15 |
| Valley Park | 14 |
| Wentzville | 14 |
| Maxville | 13 |
| Washington | 13 |
Source: NANPA central office code assignments, file dated 10/17/2026. Each prefix holds up to 10,000 numbers.
How do I dial a 636 number?
NANPA's dialling plan for 636: local calls inside the code take 7 digits, toll calls 1 + 10 digits. From another area code, dial 1 first. From abroad, use +1. The examples use 555-0147, from a range reserved for fictional numbers.
| Local call inside 636 | 555-0147 |
|---|---|
| From another US or Canadian area code | 1-636-555-0147 |
| From outside North America | +1 636 555 0147 |
| E.164, for CRMs and SMS tools | +16365550147 |
When did area code 636 start?
Area code 636 went into service on May 22, 1999, split from 314. It has no overlay, so every number in its area still starts with it.
Tools for 636 numbers
- Area code lookup
Look up any code or a whole list of numbers, or find the codes for a state or city.
- Area code time zone
Local time for a list of numbers, with a callable-now flag.
- NPA-NXX lookup
Rate center and state for one prefix, a level below the area code.
- TCPA calling hours checker
Whether it's inside the federal 8 a.m. to 9 p.m. calling window there now.
Next step
A 636 number tells you where it was issued, not what it is now.
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Area code 636 questions
- What state is area code 636?
- Area code 636 is in Missouri, United States. Its largest rate centers by number of prefixes are Saint Charles, Chesterfield, Harvester, Manchester and O'Fallon.
- What time zone is area code 636 in?
- Central Time.
- Does area code 636 have an overlay?
- Not as of NANPA's file dated 10/16/2026. Every number in its area uses 636.
- When did area code 636 start?
- Area code 636 went into service on May 22, 1999, split from 314.
- Is a 636 number a cell phone or a landline?
- The area code can't tell you. In the US and Canada mobiles, landlines and VoIP lines share area codes and prefixes, and numbers move between carriers and line types. Only a live line-type lookup answers it for one number.
- How many phone numbers does area code 636 have?
- 430 of its 792 possible prefixes are in service, and each prefix holds up to 10,000 numbers. That counts prefixes assigned to carriers, not numbers in use.
Other area codes in Missouri
Sources
Location, overlays, in-service date and dialling plan: NANPA NPA database, file dated 10/16/2026. Prefixes and rate centers: NANPA central office code assignments, 10/17/2026. Time zones mapped to the IANA time zone database. By the SimpleVerifier Team; how we build these pages.