Correctly Addressed

Address Types

How to address mail to APO, FPO and DPO

Write the unit and box number on the street line, then APO, FPO or DPO in place of the city, then the region code AA, AE or AP in place of the state, then the ZIP. Leave the country name off completely. A military address is treated as domestic mail, so adding a country sends it into the international stream and it can be returned.

Checked July 30, 2026/8 min read

Claire Post

Written by Claire PostReviewed against USPS Publication 28

What is on this page7 sections
  1. 01Step by step
  2. 02Real examples
  3. 03Quick reference
  4. 04Special cases
  5. 05Key terms
  6. 06Check before you mail
  7. 07Questions people ask

A military address looks foreign and is treated as domestic. That single fact explains almost every rule on this page.

Mail to a base overseas travels as normal US mail to a sorting point, and the military moves it the rest of the way. So the envelope has to look like a domestic address to the Postal Service, which means no country, no base name, and no city.

The handoff happens at a small number of military mail terminals inside the US, where regular USPS sorting stops and military postal handling begins. Up to that terminal, the envelope is processed exactly like a letter going to Ohio or Oregon, which is the entire reason the format has to mimic a normal US address so closely. Once it clears that terminal, the military system takes over and routes by unit and box number the way a base directory would, not by city or country the way the rest of the postal network does.

Step by step

  1. Use the full name and rank as the service member gave it

    Rank goes first, then the full legal name. Nicknames get mail returned on a base, where the roster is the only thing anyone checks against.

  2. Put the unit and box on the street line

    This replaces the street address. Copy it exactly, including the letters and the box number.

    SGT ALICE CHENUNIT 2050 BOX 4190APO AE 09811
    CorrectA soldier stationed in Europe. Region code AE.

  3. Pick the right three letters for the destination type

    APO is an Army or Air Force post office, FPO is a Navy or Marine one, and DPO is a diplomatic post office for embassy staff. The service member address tells you which.

  4. Match the region code to the part of the world

    AA covers the Americas outside the continental US, AE covers Europe, the Middle East, Africa and Canada, and AP covers the Pacific and Asia.

    PO2 BEN RUIZUSS CORAL BAYFPO AP 96667
    CorrectA sailor in the Pacific. Region code AP, FPO instead of APO.

  5. Leave the country and the base name off

    No Germany, no Japan, no base name. Those turn a domestic piece of mail into an international one, and it will come back.

A few real examples

The steps above cover the rule. These show it applied to a spread of real situations, so you can match yours to the closest one.

A1C JORDAN REYESUNIT 5510 BOX 220APO AP 96319
CorrectAn airman in the Pacific region.
SGT ALICE CHENUNIT 2050 BOX 4190APO AE 09811GERMANY
What was writtenThe country name added "for clarity." This is the single most common military-mail mistake, and it does the opposite of clarifying anything for the machine.

Quick reference

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CodeCoversExample ZIP range
AACentral and South America, the Caribbean340xx
AEEurope, Middle East, Africa, Canada090xx to 098xx
APThe Pacific and Asia962xx to 966xx
APOArmy and Air Force post officeAny of the three codes
FPONavy and Marine post officeAny of the three codes
DPODiplomatic post officeAny of the three codes

Special cases

The rule above covers most people. Here is what changes for the rest.

Can I address a package to "Any Service Member" the way people used to during past wars?

No. Mail addressed to "Any Service Member" or "A Soldier" has not been deliverable since security restrictions were put in place, and both the military and USPS will not forward it. Every piece of military mail needs one specific, named recipient. If you want to support service members generally, official military support organizations run donation and card programs that route mail correctly instead of relying on a generic address.

What restrictions apply to what I can mail to a military address?

More than a standard domestic address, because the mail is also subject to the destination country customs rules even though it ships as domestic US mail. Alcohol, aerosols, and certain foods are commonly restricted depending on the base. Always check the specific destination restrictions before mailing anything beyond a standard letter or card.

Key terms on this page

APO
Army Post Office, the designation used in place of a city for Army and Air Force installations.
FPO
Fleet Post Office, the designation used in place of a city for Navy and Marine Corps installations, including ships at sea.
DPO
Diplomatic Post Office, used for US embassy and consulate mail.
Region code
The two-letter code, AA, AE, or AP, that replaces the state on a military address. It identifies a routing group, not a specific country.
Domestic mail treatment
The USPS policy of processing military mail as ordinary US mail up to the point it reaches the military postal system, which is why it is priced and formatted like a domestic address rather than an international one.

Check the address before you mail

Questions people ask

Does military mail cost more to send?
No. APO, FPO and DPO addresses are charged as domestic mail no matter where in the world the base sits, which is one of the reasons the country name has to stay off.
Why does Canada use the AE code?
AE is not only Europe. It covers everything reached through the eastern routing, and Canada is grouped there. The letters stand for a routing group, not a continent.
How long does mail to a base take?
Plan on two to three weeks for most locations, and longer for a ship at sea. Deadlines for holiday mail are published fresh every autumn and are earlier than people expect, so check the current year rather than assuming last year date still applies.
Can I send anything I want?
No. Each destination has its own list of restricted items, and some countries restrict things the base cannot accept. Check the customs form requirements before you seal a package.
Why does adding the country name actually cause a problem instead of just being extra information?
Because military mail is processed as domestic US mail up until the point it reaches the military postal system. A country name on the envelope can cause it to be pulled into the international mail stream instead, which uses a completely different routing path and does not know what to do with an APO or FPO designation. It is not that the country name is ignored, it is that it actively sends the letter down the wrong track.
Can I track military mail the way I can track a regular package?
Tracked services are available and generally recommended for anything beyond a standard letter, since delivery times to a base or ship vary more than domestic tracking would suggest. A basic letter with just a stamp typically has no tracking at all, the same as any other First-Class letter, which is worth knowing if timing matters.
Is there an official way to send mail to troops if I do not know a specific person to address it to?
Yes, but it goes through an organization rather than directly through USPS. Groups like the USO and other vetted military support programs run structured mail and care package drives that reach service members without needing a named recipient, which is the legitimate modern version of what "any service member" mail used to do before it was restricted.
Does the unit and box number ever change while someone is deployed at the same base?
It can, particularly for a unit that rotates or reorganizes, even when the person themselves has not moved. This is different from a civilian address, where the unit number is tied to a fixed physical location. Always use the most recent unit and box information the service member has given you directly rather than reusing an old letter address, since a piece of mail with an outdated unit number can be delayed even though every other part of the address is correct.
How is a ship different from a land base when it comes to addressing mail?
The format looks identical, an FPO address with a region code, but a ship is not a fixed location the way a base is. Its mail gets routed to wherever the ship currently is through the Fleet Post Office system, which can mean genuinely longer and less predictable delivery times than a land-based APO or DPO address, especially when a ship is underway rather than in port.
Does a DPO address for embassy staff work exactly the same way as APO and FPO?
The format and the domestic-mail logic are identical, but DPO covers a smaller and more specific group, State Department and embassy personnel rather than deployed service members, and diplomatic mail can be subject to additional handling under diplomatic pouch rules that ordinary APO or FPO mail is not. For a standard letter the difference rarely matters, but for anything unusual, checking with the specific embassy mailroom is worth the extra step.

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