M I T Post Office CAMBRIDGE (MA) in Cambridge, MA

M I T Post Office CAMBRIDGE (MA)

Details

Post office address	84 Massachusetts Ave
Town/City	Cambridge
State	MA
ZIP	02139-9998
Phone	617-494-5511

The Post Office is open Monday to Friday from 10:00 am to 4:00 pm. It is closed Saturday and Sunday.

Retail

Monday
Mar 9, 2026

Open from 10:00am to 4:00pm

Tuesday
Mar 10, 2026

Open from 10:00am to 4:00pm

Wednesday
Mar 11, 2026

Open from 10:00am to 4:00pm

Thursday
Mar 12, 2026

Open from 10:00am to 4:00pm

Friday
Mar 13, 2026

Open from 10:00am to 4:00pm

Saturday
Mar 14, 2026

Closed

Sunday
Mar 15, 2026

Closed

Call Referral

Monday
Mar 9, 2026

Open from 9:00am to 5:30pm

Tuesday
Mar 10, 2026

Open from 9:00am to 5:30pm

Wednesday
Mar 11, 2026

Open from 9:00am to 5:30pm

Thursday
Mar 12, 2026

Open from 9:00am to 5:30pm

Friday
Mar 13, 2026

Open from 9:00am to 5:30pm

Saturday
Mar 14, 2026

Closed

Sunday
Mar 15, 2026

Closed

Lobby

Monday
Mar 9, 2026

Open from 12:01am to 11:59pm

Tuesday
Mar 10, 2026

Open from 12:01am to 11:59pm

Wednesday
Mar 11, 2026

Open from 12:01am to 11:59pm

Thursday
Mar 12, 2026

Open from 12:01am to 11:59pm

Friday
Mar 13, 2026

Open from 12:01am to 11:59pm

Saturday
Mar 14, 2026

Open from 12:01am to 11:59pm

Sunday
Mar 15, 2026

Open from 12:01am to 11:59pm

Pickup Services

Monday
Mar 9, 2026

Open from 10:00am to 4:00pm

Tuesday
Mar 10, 2026

Open from 10:00am to 4:00pm

Wednesday
Mar 11, 2026

Open from 10:00am to 4:00pm

Thursday
Mar 12, 2026

Open from 10:00am to 4:00pm

Friday
Mar 13, 2026

Open from 10:00am to 4:00pm

Saturday
Mar 14, 2026

Closed

Sunday
Mar 15, 2026

Closed

PO Box Access

Monday
Mar 9, 2026

Open from 12:01am to 11:59pm

Tuesday
Mar 10, 2026

Open from 12:01am to 11:59pm

Wednesday
Mar 11, 2026

Open from 12:01am to 11:59pm

Thursday
Mar 12, 2026

Open from 12:01am to 11:59pm

Friday
Mar 13, 2026

Open from 12:01am to 11:59pm

Saturday
Mar 14, 2026

Open from 12:01am to 11:59pm

Sunday
Mar 15, 2026

Open from 12:01am to 11:59pm

Report a change

Services Offered at this location and other information

Services Available:<ul><li>Call Referral</li><li>Gift Card Services</li><li>Global Express Guranteed®</li><li>Label Broker®</li><li>Money Orders (Domestic)</li><li>Money Orders (Inquiry)</li><li>Money Orders (International)</li><li>Pickup Accountable Mail</li><li>Pickup Hold Mail</li><li>Pickup Notice Left Mail</li><li>Priority Mail International®</li></ul><hr>No Parking Available<hr>TTY: 877-889-2457<hr>Phone support: 1-800-ASK-USPS® (800-275-8777)<hr>Global Express Guaranteed:<ul><li>Monday: 17:00</li><li>Tuesday: 17:00</li><li>Wednesday: 17:00</li><li>Thursday: 17:00</li><li>Friday: 17:00</li></ul><hr>Last Collection:<ul><li>Monday: 16:00</li><li>Tuesday: 16:00</li><li>Wednesday: 16:00</li><li>Thursday: 16:00</li><li>Friday: 16:00</li></ul><hr>PO Box Delivery:<ul><li>Monday: 11:00</li><li>Tuesday: 11:00</li><li>Wednesday: 11:00</li><li>Thursday: 11:00</li><li>Friday: 11:00</li></ul>

Official Website

https://www.usps.com/

Postage rates 2026

Indicative rates subject to change by the postal operator.

First-Class Mail

Delivery in 1–5 business days.

Service

Price

Postcards

From $0.61

Letters (up to 1 oz)

$0.78

Large Envelopes (Flats)

From $1.63

Shipping Services

USPS domestic shipping prices at the Post Office (retail rates).

Service

Price

USPS Ground Advantage (2–5 days)

From $7.30

Priority Mail (2–3 days)

From $10.20

Priority Mail Flat Rate Envelope

From $11.95

Priority Mail Flat Rate Box

From $12.65

Priority Mail Express (1–3 days)

From $33.00

Priority Mail Express Flat Rate Envelope

From $33.25

Media Mail (2–8 days)

From $4.47

Where is your post office located in Cambridge?

Directions View on Google Maps Satellite view

Does this post office open on saturdays?

No, the Post Office is closed on Saturdays. Check the timetables above to know when to go during the week.

Does this post office open on sundays?

No, unfortunately the Post Office is closed on Sundays. Look at next week's opening hours.

Track a package

Track my package →

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Post Offices in Cambridge

Find the list of all the other Post Offices in Cambridge by following this link.

USPS in 2026: America's most trusted federal agency modernizes for the future

The United States Postal Service (USPS) remains one of America's most trusted and essential institutions, delivering mail and packages to more than 167 million addresses across the nation — reaching every home, business, and community, six and often seven days a week. As the backbone of American communication and commerce, USPS connects urban centers, rural towns, and everything in between with reliable, affordable service.

At the heart of USPS's ongoing evolution is the ambitious Delivering for America (DFA) plan, a bold 10-year modernization strategy designed to ensure long-term sustainability and improved service. The plan is driving significant investment in infrastructure, technology, and workforce development, positioning USPS to thrive for decades to come. With a focus on operational efficiency and customer experience, the DFA plan represents one of the largest transformation efforts in the agency's history.

One of the most exciting developments is USPS Ground Advantage, a streamlined shipping service that combines the best of previous ground options into one simple, affordable product. Ground Advantage offers delivery in 2 to 5 business days with tracking and insurance included, making it a convenient and cost-effective choice for everyday shipping needs. Meanwhile, USPS Connect brings same-day and next-day delivery options to small and mid-sized businesses, helping local enterprises compete with larger retailers and serve their customers faster.

USPS is leading the way in fleet electrification with its Next Generation Delivery Vehicles (NGDVs). The agency has committed to making at least 75% of new vehicles battery-electric, transforming the world's largest civilian vehicle fleet into a greener operation. The new NGDVs feature modern amenities including air conditioning, improved ergonomics, 360-degree cameras, and advanced safety systems — a major upgrade that benefits both letter carriers and the environment.

Digital innovation is also a key pillar of USPS's modernization. Informed Delivery is a free service that gives customers a digital preview of their incoming mail each morning, along with a dashboard for tracking packages — all accessible via email or the USPS Mobile app. Combined with Click-N-Ship for buying and printing labels online and free Package Pickup from your doorstep, USPS makes shipping and receiving more convenient than ever.

Behind the scenes, USPS is building state-of-the-art Regional Processing and Distribution Centers (RPDCs) — modern logistics hubs equipped with advanced automation and sorting technology. These facilities are designed to streamline mail and package processing, reduce transit times, and expand capacity to meet growing e-commerce demand. Several RPDCs are already operational, with more planned through 2028 as part of a modern hub-and-spoke network.

USPS continues to offer some of the most affordable shipping options available. Priority Mail Flat Rate boxes and envelopes let you ship items at one price regardless of weight (up to 70 lbs) or domestic destination — and the packaging is provided free of charge. The current price of a Forever stamp is $0.78, covering First-Class letters sent anywhere in the United States. With services ranging from affordable First-Class Mail to expedited Priority Mail Express, USPS provides a shipping solution for every need and budget.

Frequently asked questions about USPS

How do I track a USPS package?

Go to USPS Tracking at usps.com and enter your tracking number (found on your receipt, shipping confirmation email, or the sender's notification). You can also track packages using the free USPS Mobile app for iOS and Android, by texting your tracking number to 28777 (2USPS), or by calling 1-800-222-1811. Most USPS services — including Priority Mail, Priority Mail Express, USPS Ground Advantage, and Certified Mail — come with tracking included.

What should I do if I missed a USPS delivery?

If the carrier could not deliver your item, they will leave a PS Form 3849 ("Sorry We Missed You" notice) in your mailbox. You can then schedule a free redelivery online at usps.com/redelivery, by calling 1-800-ASK-USPS (1-800-275-8777), or by checking the appropriate box on the notice and leaving it for your carrier. You can also choose to pick up the item in person at your local Post Office — the notice will tell you which location is holding your package and how long they will keep it (usually 15 days before it is returned to sender).

How do I forward my mail when I move?

You can submit a Change of Address (COA) request online at usps.com/move for a small identity verification fee of $1.10 charged to a credit or debit card. You can also fill out PS Form 3575 at any Post Office. USPS will forward most First-Class Mail and packages to your new address for 12 months, and periodicals for 60 days. Standard Mail (marketing mail) is generally not forwarded. Submit your request at least two weeks before your move to ensure a smooth transition.

What is the difference between Priority Mail and First-Class Mail?

First-Class Mail is used for standard letters (up to 3.5 oz), large envelopes/flats (up to 13 oz), and small packages (up to 13 oz). Delivery typically takes 1 to 5 business days depending on distance. Priority Mail is designed for faster delivery of packages and thick envelopes, with an expected delivery time of 1 to 3 business days. Priority Mail includes free USPS packaging (Flat Rate boxes and envelopes), up to $100 of insurance, and USPS Tracking. Priority Mail has no weight limit for Flat Rate options. For the fastest guaranteed service, Priority Mail Express offers overnight to 2-day delivery with a money-back guarantee.

What are the weight and size limits for USPS shipments?

For domestic mail, the maximum weight is 70 lbs for all package services. Maximum combined length and girth (distance around the thickest part) is 108 inches for most services and 130 inches for USPS Ground Advantage. First-Class Mail letters must be at least 5" x 3.5" and no larger than 6.125" x 11.5" x 0.25" (up to 3.5 oz). First-Class Mail large envelopes (flats) can be up to 15" x 12" x 0.75" and weigh up to 13 oz. Items exceeding 13 oz must be sent as packages via Priority Mail, USPS Ground Advantage, or another package service.

How do I file a complaint with USPS?

You can file a complaint or submit feedback online through the USPS Customer Care Center, or by calling 1-800-ASK-USPS (1-800-275-8777). For issues with specific mail or packages, have your tracking number ready. You can also visit your local Post Office and speak with the station manager. If your issue is not resolved, you can escalate it to the USPS Office of Inspector General (OIG) at uspsoig.gov or contact the Postal Regulatory Commission (PRC) to file a formal complaint.

Do I need customs forms for international mail sent through USPS?

Yes, all international packages and most large envelopes sent through USPS require a customs declaration form. Items valued at $400 or less use the small PS Form 2976 (CN 22), while items over $400 or those requiring detailed descriptions use the larger PS Form 2976-A (CN 23). You must accurately describe the contents, declare the value, and indicate whether the shipment is a gift, commercial sample, or merchandise. You can fill out customs forms online using USPS Customs Forms Online or at the Post Office counter. Failure to include the correct customs documentation can result in delays, return, or seizure of your item.

How do I hold my mail while I am away?

USPS offers a free Hold Mail service that lets you pause delivery for 3 to 30 days. You can request a mail hold online at usps.com/holdmail, by calling 1-800-ASK-USPS, or by submitting PS Form 8076 at your local Post Office. When the hold period ends, you can choose to have all accumulated mail delivered on a specific day or pick it up in person at the Post Office. This service is ideal for vacations or business trips and helps prevent mail from piling up in your mailbox, which can be a security concern.

Useful tips for using USPS

Use Click-N-Ship to buy and print shipping labels from home. You can compare rates across services like Priority Mail, USPS Ground Advantage, and Priority Mail Express, pay online with a credit card or PayPal, and schedule a free package pickup from your mailbox or doorstep. Commercial pricing through Click-N-Ship often offers significant discounts compared to retail counter prices, especially for Priority Mail and international shipments.

Sign up for Informed Delivery, a free service that sends you grayscale images of the exterior of your incoming mail each morning via email or the USPS app. You can also see the status of incoming and outgoing packages in one dashboard. It is an excellent way to know what to expect in your mailbox each day, monitor for missing mail, and manage deliveries while you are away from home.

You can schedule a free Package Pickup online through USPS. Your letter carrier will collect your prepaid packages right from your doorstep during regular delivery — no need to drive to the Post Office. Pickups can be scheduled for the next delivery day, and there is no limit on the number of packages. This service works with Priority Mail, Priority Mail Express, USPS Ground Advantage, and international shipments.

The free USPS Mobile app lets you track packages, view Informed Delivery scans, find Post Office locations and hours, schedule redelivery, calculate prices, look up ZIP Codes, and even scan barcodes on packages for instant tracking. The app also lets you set delivery preferences and get real-time push notifications on your shipments.

If you need to visit the Post Office, try to go mid-week (Tuesday through Thursday) and mid-morning or early afternoon to avoid the longest lines. Mondays, Saturdays, lunch hours, and the days around holidays tend to be the busiest. Many routine tasks — buying stamps, scheduling pickups, printing labels, submitting hold mail requests — can be done entirely online, saving you a trip altogether.

Take advantage of USPS Flat Rate shipping for heavy items. With Priority Mail Flat Rate boxes and envelopes, you pay one price regardless of weight (up to 70 lbs) or domestic destination. A Medium Flat Rate Box costs around $16–17 and a Small Flat Rate Box around $10, making them excellent value for dense or heavy shipments. USPS provides the Flat Rate boxes and envelopes for free — you can order them online at usps.com/freeboxes or pick them up at any Post Office.

This website is an independent information directory and is NOT the official website of the postal service. We are not affiliated with, endorsed by, or connected to any postal operator. The information provided on this page is for general informational purposes only, may contain errors or be outdated, and does not constitute advice of any kind. We accept no liability whatsoever for any inaccuracy, missing information, or any loss or damage arising from the use of this information. Use at your own risk. For official and up-to-date information, please contact the postal operator directly or visit their official website.