Direct Mail

Can Certified Mail Be Sent to a PO Box

By 27 July 2023April 15th, 2024No Comments
certified mail be sent to a po box

Can Certified Mail Be Sent to a PO Box

If you have used the USPS services, you probably already know about their popular mailing options like First Class Mail, Priority Mail, etc.

Though these options are widespread, you cannot track them or get a delivery confirmation. Hence, many people wonder if they can upgrade these mailing classes in some way.

Fortunately, they can!

certified mail be sent to a po box

Certified Mail and Registered Mail are two such options that help you track your mail items and get proof of mailing. You can add these top-ups for an additional fee to your regular mailing class.

These options are the most helpful when you need to mail crucial documents like tax forms, legal forms, invoices, checks, etc. If necessary, they enable you to prove that you mailed a particular document on a specific date. Thus, the recipient won’t be able to deny receiving the mail.

But, there are many questions among the USPS customers, like – Can you send Certified Mail to a PO box? Again, you can!

However, the process is not the same as sending Certified Mail to residential and commercial addresses. It’s a little longer, but it’s worth it.

Below, we have enlisted some more details about Certified Mail. Also, we have covered the steps on how to send mail to a PO box.

What Is Certified Mail?

Certified Mail is a USPS service that allows the sender to obtain a mailing receipt and online verification saying that your mailpiece was delivered. You can also request signature confirmation so that you can know who received the mail.

In short, individuals and companies use this option for several reasons, including:

  • Mailing documents with sensitive information
  • Storing evidence that you sent something
  • Getting a physical or electronic delivery confirmation

Certified Mail allows you to track the movement of your mailpiece throughout the USPS system.

This service was first introduced in 1955 by Gen. Joseph Cooper, the Assistant US Postmaster of that time. He aimed to establish a trackable and reliable mailing solution for businesses and individual persons.

Naturally, the service has been modified many times throughout the years, but its prime objective remains the same. It is still known for offering proof of transit and delivery to both the sender and receiver.

Since the intended recipients are also aware of the incoming mailpiece, they can make themselves available to receive it. This further safeguards your mail item and assures that it gets to the right hands.

For more safety, you can add other extras to your Certified Mail. Some of these extras include a Return Receipt which you can get for an extra fee. It is a small, postcard-sized green card mailed back to the sender after their Certified Mail letters or packages are delivered.

The USPS itself completes the delivery of these green cards to you through First-Class Mail. It also stores these receipts in its records for up to two years. Hence, in case of any legal disputes, you can use this proof of delivery as evidence in court.

Certified Mail can help you get the following services: 

  • Refund: You can claim a refund if you don’t receive the electronic verification and mailing receipt even after 30 days of sending a Certified Mail item. But, you will only get a refund on the service fee, not the postage. Also, some items are exempt from refunds, which you need to check before mailing.
  • Mailing receipt: When you take your mailpiece to the post office and pay the charges, you are given a mailing receipt that has an 18-digit tracking number.
  • Delivery record: All Certified Mail deliveries require the recipient’s signature. If there is no one to sign for it, the postal worker does not deliver your mail. This signature is called the record of delivery.
  • Proof of signature: It is another name for Return Receipt. You can choose if you want this receipt physically or electronically.
  • Delivery status: You can track your mail and view the delivery status by calling the USPS office, on their website, or through Bulk Electronic File Transfer.

You can send Certified Mail to any postal address in the US. But, there is still a lot of speculation regarding whether can you send a certified letter to a PO box. Others also ask- can you send registered mail to a PO box?

Let’s dig in for more!

Also Read: How to Address Mail to A PO Box for Business Use Cases(Opens in a new browser tab)

Steps to Send Certified Mail

You first need to buy the Certified Mail slip, also known as PS form 3800. Fill in all the details like the delivery address and postage. If you are filling out this form online, you may need to provide proof of identification.

Once filled, take it to the counter with your letter or parcel. Select a delivery option best suited to you and get the tracking number.

If you want to ensure the deliverability of your mailpiece, you can ask for proof of delivery. The USPS will then take a signature from the recipient while delivering the mail and notify you about it. Also, you may ask for email notifications if that’s convenient for you.

But, if you select this option, you need to ensure that there will be someone present at the destination to sign for your mail. Some of the Certified Mail options (which we will discuss below) also help you assure that only a specific person receives your mail.

Hence, you can customize your mailing according to the level of security you need for your letter.

Also, you can see as your letter is moving from one location to another. Such real-time updates help you coordinate with the receiver and help them be available at the correct date and time.

If your mail is rejected or nobody is available to receive it, you receive the notification immediately. Then, you can call the recipient or take any other steps as you see fit.

Coming to the question- Can you send a registered letter to a PO box?

Please note that Registered Mail deliveries to a PO box also work in the same way. The only difference between Registered Mail vs. Certified Mail is that Registered Mail is more secure as your mailpieces are sealed in tightly shut containers.

Related Article: PO Box–Only ZIP Codes

Can You Send Certified Mail to a Post Office Box?

As we said earlier, the answer to the question ‘Can you send Certified Mail to a PO box USPS’ is yes. You can send a Certified Mail item to any domestic address you want, but the process of obtaining the recipient’s signature changes somehow.

Typically, the address recipient or someone available at the mailing address signs while receiving the mail. But, who signs for Certified Mail to a PO box as there is nobody available at the mailbox location?

Luckily, the USPS has a solution to this problem. Postal workers do not carry your mailpiece to the PO box address. They leave it back at the post office for the recipient to collect by themselves.

The worker leaves a notification card (PS Form 3849) inside the PO box instructing the recipient about collecting their mail.

Thus, the recipients only receive a notification card in their PO boxes. They can take the card to the window clerk at the post office and request their mailpiece.

The clerk will then give them a delivery confirmation signature card (PS form 3800) to sign on and collect the mail. The USPS will capture and record this signature electronically.

If you have requested a Return Receipt, this card is sent to you via First-Class Mail.

When talking about an electronic Return Receipt, the recipient must sign on an electronic pad. The USPS turns it into an online receipt sent to you in the form of a PDF document.

Electronic Return Receipts are a great way of saving money. Also, they are easier to store and manage for a long time. On the other hand, traditional green cards can get lost or misplaced.

In short, you don’t need to worry about sending Certified Mail to PO boxes. The United States Postal Services has made it a breeze.

Hence, people or companies with PO box addresses can also receive Certified Mail with ease.

But, while sending Certified Mail, assure that the recipient picks up the mail envelope within 15 days. The USPS does not store unclaimed Certified Mail for more than this period.

If you cannot collect the mail, you can give the notification card or slip to a friend or relative. They can collect it on your behalf, provided the sender did not select the Restricted Delivery option.

Also Read: Direct Mail Automation Software

Sending Certified Mail to Virtual Mailboxes

If you want to avoid going to the post office to collect your mail or for any other reason, consider virtual mailboxes. Though these mailboxes sound like they work entirely online, they are physical mailboxes located at physical addresses. The only difference is that you can access or operate them virtually, without going anywhere.

Virtual mailboxes are a blessing for people who don’t have the time to go back and forth to the post office and seek convenience. You can access them online on any internet-enabled device like a computer or mobile phone.

Such mailboxes give you the modern mailing experience that is not possible with traditional mailboxes or PO boxes. You are notified about any mail you receive and can also access scanned copies of it.

But, you may be still wondering how can Certified Mail be sent to a PO box that is virtual. Who is going to sign for it?

Well, there is a full-time employee at the location who signs for the mail on your behalf and uploads it to your virtual mailbox. You will get a notification saying you have a letter or package in your mailbox, which you can now access online.

Hence, you still need someone to sign for a Certified Mail item sent to a virtual mailbox.

If you want mail forwarding services, check with your virtual mailbox service provider beforehand. Usually, they forward your mail at a discounted postage to any mailing address in the US.

Also Read: International Address Verification

How to Address a Letter to Be Sent to a PO Box

For sending a letter to a PO box, you should mention the PO box address instead of the street address. Find below the USPS format to write a PO box address correctly:

Begin with the recipient’s name as usual. If you are mailing a company, the intended recipient’s name comes on the first line and the company name on the following line.

But, you may not mention the company name as it does not make any difference. Alternatively, you may mention the company name and not the recipient name. The mail carrier will drop the notification card in the mentioned PO box number irrespective of the name written on the mailpiece.

On the following line, write the PO box number. The number ranges between two to five digits — for example, PO box 10598. Since the USPS advises not using punctuation marks, avoid writing it as ‘P.O. box.’

The last line of your mailing address remains the same. Start with the city name, followed by the state abbreviation and the ZIP code. If possible, use ZIP+4 codes as they increase the chances of your mail delivery.

Therefore, a PO box address should look like this:

PO BOX 16923

Please remember to follow the general USPS address guidelines like writing in uppercase letters.

Also, below are some more details about the USPS Certified Mail service to help you understand it in-depth.

Also Read: Address Verification Software

Can You Use the Certified Mail Option for All USPS Mailing Classes?

You can avail of the Certified Mail option only for three USPS mailing classes, and they are:

  • First-Class Mail
  • First-Class Package Service-Commercial
  • Priority Mail

You can also send Certified Mail to DPO/ FPO/ APO locations. But, there are some locations where you cannot send Certified Mail and cannot avail of any delivery information. So, please check with your local post office before sending out anything to military bases.

How Long Does Certified Mail Take to Deliver?

The speed at which your Certified Mail items reach the destination depends on the mailing class you select.

The USPS takes around one to five business days to deliver First-Class Mail items—both letters and packages. If you opt for a Return Receipt, it will also be sent to you via First-Class Mail. So, please wait for a few days to get your Receipt.

Priority Mail deliveries take only one to three business days. Hence, you should prefer this option for faster and safer mailing.

The prime reason you should opt for Certified Mail is that the mailpiece is either important or offers proof of mailing. Thus, it makes sense to choose Priority Mail to further help you get your items speedily and safely delivered.

Priority Mail plus Certified Mail is the best option to select. But, if you are on a tight budget and want to save some extra bucks, First-Class Mail may be the ideal choice.

Also Read: Bulk Batch Address Verification and Validation

Which Certified Mail Options Should You Consider While Mailing to a PO Box?

Can you send Certified Mail to a business PO box? Yes, it is advisable to send Certified Mail to business PO boxes to guarantee that your mail reaches the intended recipient.

PO boxes assigned to businesses often have a lot of people authorized to collect mail from the box. Hence, when you send something to a business PO box, ensure that it gets to the correct person. Perhaps, the only way to do that is to use Certified Mail.

The following Certified Mail options can help you add more security to your mailpieces:

  • Certified Mail Restricted Delivery: As the name goes, you may restrict the delivery of your Certified Mail item. You can direct the letter carrier to hand over the mail only to the addressed recipient (or an authorized agent) with this option. Therefore, nobody else can show up at the post office with the notification card and collect the mail.
  • Certified Mail Adult Signature Required: You can direct your mail delivery only to an adult who is 21 years or older. However, this option is not very secure, and any adult can collect your mail.
  • Certified Mail Adult Signature Restricted Delivery: Using this option, you can restrict the delivery only to the addressee or an authorized agent who is an adult. This option is only available to commercial printed mailers or those who bought the service online.

After you select the options and pay the fees, the clerk gives you a receipt with the tracking number on it. You can enter this number on the USPS website to track your mail item. But, it may take some time to show up, so wait for at least a day after mailing for the tracking details to appear on the site.

Also Read: Address Verification API

Certified Mail Cost

The standard rate of availing of the Certified Mail option is $3.75. Note that it does not include the postage fee.

First-Class Mail rates start at $0.40 for postcards and $0.58 for letters. You can calculate your postage depending on the weight of your mailpiece and the destination. Then, add this $3.75 to get the postage cost.

But, the price can increase further if you opt for any additional services.

Find below the prices of Certified Mail optional extras:
Adult Signature: $9.75
Restricted Delivery: $9.75
Adult Signature Restricted Delivery: $9.75

Priority Mail costs a little more than First-Class Mail. But, it is still a reasonable postal fee to mail something urgently.

Mailing to PO boxes doesn’t change the pricing. The postage is still calculated depending on the mail weight and destination.

What Items Are Restricted or Prohibited to Send Via Certified Mail?

Though you can mail to any valid address in the US via Certified Mail, there are some items that you cannot send. There are certain restrictions and prohibitions on certain items as they are either dangerous or illegal. 

Some USPS prohibited items in the US are:

  • Ammunition
  • Gasoline
  • Air Bags
  • Marijuana (medical and otherwise)
  • Explosives, etc. 

Also, find below some restricted items that you cannot send through the Certified Mail and other USPS mailing options:

  • Aerosols
  • Cigarettes, Cigars, & Tobacco
  • Dry Ice 
  • Firearms
  • Cremated Remains
  • Fragile Items
  • Hand Sanitizer
  • Glues
  • Alcoholic Beverages
  • Hemp Products (including CBD)
  • Live Animals
  • Lithium Batteries
  • Medicines & Prescription Drugs
  • Poisons
  • Matches
  • Nail Polish
  • Perfumes
  • Paint
  • Perishable Items

Before pondering on how to send Certified Mail to PO boxes, consider the type of item you want to mail. Any USPS mailing class cannot send the above items. So, you may have to check whether any private couriers like DHL or FedEx are delivering them. 

If you want to avoid going to the post office to send your Certified Mail and other items, try online direct mail services like PostGrid. Our API can help you create, print, and mail altogether without going to the post office even once.  

More On PostGrid’s Direct Mail API

PostGrid’s direct mail API is not restricted to only sending Certified Mail. You can mail your postcards, letters, invoices, etc., and also avail of the different USPS services without taking any effort.

Find some of our most popular features below:

In-Built Design Templates

Want to draft a letter or design a creative for your marketing postcards? PostGrid enables you to do that without the help of a designer. Our API has many in-built templates that you can select and get started. You can also add any customization and variable features if you need them.

On-Demand and Bulk Mailing

You can print and mail either on-demand or in bulk. Our API is scalable, and it doesn’t matter if you want to send one item or a couple thousand. Either way, you can get our services at affordable rates.

There is no need to buy an expensive printer or stock up on perishables like ink, paper, etc. PostGrid does all the printing work on your behalf through its printing partners spread all across the US. This way, you can get your letters, cards, and other mailpieces printed in high quality and at very reasonable costs.

After printing, we can also help you send your items via the USPS. And the good news is that you get to handle all of these activities right on your system.

Track and Get Campaign Reports

Track your mail in real time with PostGrid. You can get a list of all the mail items you sent through your dashboard. So, you don’t need to visit the USPS website and manually enter any tracking numbers.

Moreover, you get to access all your campaign reports and insights through the dashboard as well helping you improve your future campaigns.


We hope you got the answer to the question- can you send Certified Mail to a PO box IRS? It is true that the receiver has to undertake a few extra steps to retrieve their package or letter. But, the safety that Certified Mail offers to your mailpieces compensates for it.

To help you make your print and mail processes easier, PostGrid assists you from start to finish. Hence, you can change the face of your offline mailing activities by automating them with us.

There are many more features of PostGrid’s direct mail API than what we listed above. Click here to sign up and know how to send Certified Mail to PO boxes and so much more.

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