Cos Cob Post Office

152 E Putnam Ave, Cos Cob, CT 06807

Contact Numbers

Phone: 203-869-1470
TTY: 877-889-2457
Toll-Free: 1-800-Ask-USPS® (275-8777)

Retail Hours

Lobby Hours
PO Box Access Available

Monday 24 hours
Tuesday 24 hours
Wednesday 24 hours
Thursday 24 hours
Friday 24 hours
Saturday 24 hours
Sunday 24 hours

Last Collection Times

Monday 5:00pm
Tuesday 5:00pm
Wednesday 5:00pm
Thursday 5:00pm
Friday 5:00pm
Saturday 1:00pm
Sunday Closed

*This facility does not process US Passports applications or renewals. Check nearby locations below.

  • Burial Flags
  • Business Line
  • Duck Stamps
  • General Delivery
  • Money Orders (Domestic)
  • Money Orders (Inquiry)
  • Money Orders (International)
  • Pickup Accountable Mail
  • Pickup Hold Mail
  • PO Box Online
  • Street Parking

Visit our Links Page for Holiday Schedule, Change of Address, Hold Mail/Stop Delivery, PO Box rentals and fees, and Available Jobs.

*Please call to verify information. Is anything incorrect? Let us know here

Nearby Post Offices:

1273 E Putnam Ave
1.0 mile away

Downtown Greenwich
44 Amogerone Crossway
1.1 miles away

Old Greenwich
36 Arcadia Rd
1.4 miles away

427 West Ave Rm 334
1.7 miles away


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To the Post Master Jacob, I spoke to you on Wednesday 29th April to cancel the 'Hold Mail' for 133 River Road. And I spoke to the carrier on Wednesday 6th May to make sure he knew we should be getting mail delivered. Yesterday, the carrier said we have mail waiting at the post office. I am confused, I have tried calling you all morning and the line is constantly busy. Please can you start delivering the mail to 133 River Road. Thank you.


I live at 3 Strickland Rd. Apt. 1...I am constantly receiving mail that belongs to other people...On a regular basis my neighbors are receiving pkgs that belong to me...when I track my pkgs on internet it states there was no access to my apt...that is a downright lie...happens over and over entrance door is always unlocked with a note left on door to notify postal services....I would appreciate something done about this problem..thank you..Cos Cob


Dear Postmaster, The purpose of this correspondence is to bring to your attention a major problem with your Mail service to Rocky Brook Condo Complex in Cos Cob. When ever the mail is delivered in the box the Postman NEVER looks in the box FIRST to pick up stamped mail to go!! This is unacceptable as it has been going on for some time! I demand you correct this problem immediately! Thank you.......Cos Cob,CT.

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