Priority Post Box Finder



A post box (British English; also written postbox; also known as pillar box), also known as a collection box, mailbox, letter box or drop box (American English) is a physical box into which members of the public can deposit outgoing mail intended for collection by the agents of a country's postal. Go to your local Post Office, or you can submit the request online at the USPS Missing Mail Search, it is advised to submit one if you haven’t received your mail within seven business days. USPS will send you an email confirmation when they receive your request and begin their search.

USPS Priority Mail Flat Rate boxes are an easy-to-use, cost-effective shipping option. You can easily ship like the experts; just know the USPS Flat Rate box sizes, prices, and how it works before you buy.

How Does USPS Flat Rate Shipping Work?

The USPS Priority Mail Flat Rate service will ship your package anywhere in the U.S. in 1-3 business days for a flat fee. To ship with this service, follow these easy steps:

  1. Order free Flat Rate boxes from the USPS. You have to use the branded Flat Rate boxes to get the Flat Rate shipping price, and you can order them online or pick them up at your local Post Office.
  2. Sign up for a free Shippo account to access the best rates on USPS Flat Rate shipping and print your labels from the comfort of your office or home.
  3. Bonus! Determine if a USPS Flat Rate box is the cheapest option for the items you’re looking to ship, since it’s not always the most affordable choice.

What are the 2021 USPS Flat Rate Box Sizes and Prices?

As you’ll see below, Shippo offers discounted shipping rates when compared to what you’d find at your local Post Office. No volume or coding requirements. To sign up for a free Shippo account, visit www.goshippo.com/register/.

Finder
2021 USPS Priority Mail Flat Rate
Shippo vs. Retail Rates
ProductsDimensionsShippo Rate Retail RateSavings Using Shippo vs. Retail

% Savings with Shippo

Flat Rate Envelope12 ½” x 9 ½”$7.40$7.95$0.557%
Legal Flat Rate Envelope15” x 9 ½”$7.70$8.25$0.557%
Padded Flat Rate Envelope12 ½” x 9 ½”$8.00$8.55$0.556.5%
Small Flat Rate BoxOutside:

8 11/16” x 5 7/16” x 1 ¾”

Inside:
8 ⅝” x 5 ⅜” x 1 ⅝”

$7.90$8.45$0.556.5%
Medium Flat Rate Box – 1 (Top-Loading)Outside:

11 ¼” x 8 ¾” x 6”

Inside:
11” x 8 ½” x 5 ½”

$13.75$15.50$1.7511%
Medium Flat Rate Box – 2 (Side-Loading) Outside:

14” x 12” x 3 ½”

Inside:
13 ⅝” x 11 ⅞” x 3 ⅜”

$13.75$15.50$1.7511%
Large Flat Rate BoxesOutside:

12 ¼” x 12 ¼” x 6”

Inside:
12” x 12” x 5 ½”

$19.30$21.90$2.6012%

Is Priority Mail the Same as Flat Rate?

USPS Priority Mail is one of the most-popular service levels the Postal Service offers, and for good reason. It’s cost effective and encompasses three widely-used shipping options: Priority Mail Flat Rate (which we discuss above), Priority Mail weight-based, and Priority Mail Cubic.

To ship via Flat Rate, you need to use the Flat Rate branded boxes. To use Cubic and weight-based options, you will need to use your own packaging or USPS Priority Mail boxes.

Which is Cheaper: Flat Rate or Priority Mail?

Generally speaking, the USPS Flat Rate boxes are a great option for heavy items that are traveling long distances. We ran the numbers to find out exactly when you should use a Flat Rate box and when you should use your own packaging and ship via USPS Priority Mail weight-based or Cubic instead.

When to Use USPS Flat Rate Envelopes

  • USPS Flat Rate Envelopes are almost ALWAYS the cheapest option.
  • However, use your own envelope for packages weighing exactly 1 lb. and traveling locally.
  • And if your package weighs less than 1 lb., use your own envelope and ship via USPS First-Class Package Service.

Priority Postbox Finder Usps

Use your own envelope (NOT a Flat Rate envelope) for the following scenarios:

Flat Rate Envelope (12 1/2″ x 9 1/2″) – $7.40
Qualifications for Using Own PackagingCost to ShipSavings
Weighs 0.5-1 lb. and traveling less than 50 miles (Zone 0,1,2)$7.16$0.24
Legal Flat Rate Envelope (15″ x 9 1/2″) – $7.70
Qualifications for Using Own PackagingCost to ShipSavings
Weighs 0.5-1 lb. and traveling less than 600 miles (Zone 0-4)$7.16 – $7.67Up To $0.54
Padded Flat Rate Envelope (12 1/2″ x 9 1/2″) – $8.00
Qualifications for Using Own PackagingCost to ShipSavings
Weighs 0.5-1 lb. and traveling less than 600 miles (Zone 0-5)$7.16 – $7.88Up to $0.84
Weighs 2 lbs. and traveling less than 50 miles (Zone 0,1,2)$7.79$0.21

When to Use USPS Flat Rate Boxes

Priority Postbox Finder Zip

  • For 1 – 20 lb. packages, choose Flat Rate for long distances and your own box for short distances.
  • For <1 lb. packages, use your own box and ship via USPS First-Class Package Service.
  • For >20 lb. packages, use a Flat Rate box.

Use your own box (NOT a Flat Rate box) for the following scenarios:

Sm. Flat Rate Box (8 5/8″ x 5 3/8″ x 1 5/8″) – $7.90
Qualifications for Using Own PackagingCost to ShipSavings
Weighs 0.5-20 lbs. and traveling less than 600 miles (Zone 0-4)$7.16 – $7.81Up to $0.74
Med. Flat Rate Box (11 1/4″ x 8 3/4″ x 6″) – $13.75
Qualifications for Using Own PackagingCost to ShipSavings
Weighs 0.5-2 lbs. and traveling anywhere except U.S. Territories (Zone 0-8)$7.16 – $11.69Up to $6.59
Weighs 3-20 lbs. and traveling less than 1400 miles (Zone 0-6)$8.00 – $13.58Up to $5.75
Lg. Flat Rate Box (12 1/4″ x 12 1/4″ x 6″) – $19.30
Qualifications for Using Own PackagingCost to ShipSavings
Weighs 0.5-1 lb. and traveling to any U.S. State including Hawaii and Alaska$7.16 – $11.69Up to $12.14
Weighs 2-4 lbs. and traveling anywhere except U.S. Territories (Zone 0-8)$7.79 – $18.96Up to $11.51
Weighs 5-20 lbs. and traveling less than 1800 miles (Zone 0-7)$8.20 – $18.08Up to $11.10

Keep in mind that the maximum weight is 70 pounds. And, when sealing a Flat Rate envelope or box, the container flaps must be able to close within the normal folds.

Is Priority Mail (Weight-based) or Flat Rate Faster?

Technically speaking, they are all part of the Priority Mail mail stream, so they all ship within 1-3 business days.

Are There Any Other Restrictions?

There are specific regulations and standards for mailing restricted, prohibited, and hazardous materials, including cigarettes and smokeless tobacco. You also can’t ship airbags, ammunition, explosives, or gasoline. For more details, visit the USPS Shipping Restrictions page.

How Do I Get a USPS Priority Mail Flat Rate Label?

It takes just a few minutes to set up a free Shippo account, and then you can print the label from your office or warehouse. (To get a clearer picture upfront of how you can save on USPS shipping rates by using Shippo, feel free to check out our USPS shipping calculator.) Affix the label to the USPS Priority Mail Flat Rate box. Then, put it in your mailbox or schedule a pick-up with your local mail carrier in the Shippo dashboard.

Make sure the label you’re using matches the packaging. For example, if you are using a Priority Mail Express Flat Rate box, you need to use a Priority Mail Express Flat Rate label.

If you liked this post, you may also be interested in a video that our co-founder Laura Behrens Wu did with the co-founder of packaging solution company Lumi on shipping with the USPS.

Shippo is a multi-carrier API and web app that helps retailers, marketplaces, and platforms connect to a global network of carriers. Businesses use Shippo to get real-time rates, print labels, automate international paperwork, track packages and facilitate returns. Shippo provides the tools to help businesses succeed through e-commerce shipping.

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What USPS postal class should I use to ship to my APO/FPO location?

APO Box customers have two US Postal Service (USPS) parcel shipping options to select from for your APO/FPO/DPO shipments. Each of the postal classes has different cost and speed advantages. At APO Box you can select the default shipping class you want via your customer control panel or via custom shipping requests for specific boxes.

Priority Mail®

Priority mail is the USPS Airmail shipping method for package up to 108″ Length + Girth and under 70 pounds

Details:

This is the USPS fastest parcel shipping method to your APO/FPO address.
Packages will arrive to most locations in under two weeks.
USPS Priority mail rates can be very expensive for large or heavy packages (often over 30 USD).
The USPS charges dimensional rate on any box over 1 cubic foot
Can be used only to ship packages up to 108″ LWG and up to 70 pounds.
Pricing:

Customer pays USPS Priority postage rate based on package size and weight
Customer pays parcel insurance
Customer pays APO Box Handling fee (based on weight. See Price Page for more details)

Priority
Parcel Post®

Parcel Post is the USPS surface only method for packages up to 130″ Length + Girth and under 70 pounds. This method is good for large and oversize packages, or for lower rates for shipping.

How to measure package size (Length + Girth):

Maximum weight: 70 pounds.
Length = longest side of the box
Girth = H+W+H+W (measurement around the the box)