San Mateo to Chicago time converter
Chicago is 1 hour behind San Mateo. When it is 9:00 AM in San Mateo, it is 8:00 AM in Chicago.
3:48 PM in San Mateo, Wednesday, October 21, 2026
San Mateo to Chicago conversion table
Every hour of today in San Mateo and the matching time in Chicago. Light rows are typical working hours (9:00–18:00).
| San Mateo | Chicago |
|---|---|
| 12:00 AM | 11:00 PM−1 day |
| 1:00 AM | 12:00 AM |
| 2:00 AM | 1:00 AM |
| 3:00 AM | 2:00 AM |
| 4:00 AM | 3:00 AM |
| 5:00 AM | 4:00 AM |
| 6:00 AM | 5:00 AM |
| 7:00 AM | 6:00 AM |
| 8:00 AM | 7:00 AM |
| 9:00 AM | 8:00 AM |
| 10:00 AM | 9:00 AM |
| 11:00 AM | 10:00 AM |
| 12:00 PM | 11:00 AM |
| 1:00 PM | 12:00 PM |
| 2:00 PM | 1:00 PM |
| 3:00 PM | 2:00 PM |
| 4:00 PM | 3:00 PM |
| 5:00 PM | 4:00 PM |
| 6:00 PM | 5:00 PM |
| 7:00 PM | 6:00 PM |
| 8:00 PM | 7:00 PM |
| 9:00 PM | 8:00 PM |
| 10:00 PM | 9:00 PM |
| 11:00 PM | 10:00 PM |
Best time to call or meet
Both sides are at work from 10:00 AM – 6:00 PM in San Mateo (9:00 AM – 5:00 PM in Chicago).
Daylight saving time and the difference
The difference changes during the year because San Mateo and Chicago switch clocks on different dates:
- Oct 21, 2026 – Nov 1, 2026: -1h
- Nov 1, 2026 – Mar 14, 2027: -2h
- Mar 14, 2027 – Oct 21, 2027: -1h
Distance
San Mateo and Chicago are 4,034 km (2,507 miles) apart in a straight line.
More conversions
Questions and answers
What is the time difference between San Mateo and Chicago?
Chicago is 1 hour behind San Mateo.
What time is it in Chicago when it is 9 AM in San Mateo?
When it is 9:00 AM in San Mateo, it is 8:00 AM in Chicago.
When is the best time to call Chicago from San Mateo?
Both sides are at work from 10:00 AM – 6:00 PM in San Mateo (9:00 AM – 5:00 PM in Chicago).
Does the time difference between San Mateo and Chicago change?
Yes, for part of the year, because daylight saving time starts and ends on different dates or applies on one side only.