636 area code
St. Charles area, Central Time.Area code 636 covers St. Charles, Chesterfield, Harvester and 43 more places in Missouri, on Central Time.
Right now in St. Charles
Central Time (CST, UTC-6; CDT, UTC-5 in summer)
Calling hours: Every day, 8 AM to 9 PM (the federal rule)
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Where 636 numbers come from
Numbers are issued by rate center, a billing area named for its main town. 636 has 46. Each one's share is how many 636 numbers start there. Its biggest metro area is St. Louis, MO-IL.
- St. Charles10%
- Chesterfield8%
- Harvester8%
- Manchester6%
- O'Fallon6%
- Fenton4%
- Festus Crystal City4%
- St. Peters3%
- Valley Park3%
- Wentzville3%
- Maxville3%
- Washington3%
Also: Union, High Ridge, Troy, Imperial, Warrenton, Cedar Hill, De Soto, Pond, Portage Des Sioux, Antonia, Dardenne, Pacific + 22 more
Share of exchanges (blocks of 10,000 numbers). Source: NANPA rate center and exchange reports, November 10, 2026
When can you call a 636 number?
Sales calls to homes and cell phones have legal hours, set by the federal rule. Hold every 636 number to them, since you can't tell a work line from a personal cell.
What applies to 636Every day, 8 AM to 9 PM
- 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)
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 636 area code
636 went into service on May 22, 1999, split off from 314. Local calls can still be dialed with 7 digits.
- 1999636 starts
Source: NANPA area code database
Calling a list of 636 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.
636 area code FAQ
What area code is 636?
636 is a Missouri area code for St. Charles, Chesterfield, Harvester, Manchester and 42 more places.
What time zone is the 636 area code in?
Central Time (CST, UTC-6; CDT, UTC-5 in summer).
What are the calling hours for 636 numbers?
Every day, 8 AM to 9 PM, local time, under the federal rule.
When did the 636 area code start?
On May 22, 1999. It was split from 314.
Calling 636 numbers? Reach more of them.
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