How Many Stamps Per Ounce?

Ready to send out your mail? How much postage will you need? Read more below.

While sending letters these days is a lot less common than sending an email (or a text message), it’s still important to know how to drop a letter in the post – as well as how to make sure that you have enough stamps attached to get it to its ultimate destination!


The USPS made the process of figuring out postage significantly easier back in 2007 when they introduced the Forever Stamps. The stamps became the “gold standard” for first-rate postage in 2011, and today it’s a whole lot harder to purchase stamps for envelopes that aren’t Forever Stamps!


If you want to be sure that you always have postage covered when you drop a letter in the mail come avoiding the dreaded “Returned to Sender” issue that some people have to contend with – delaying your letter at the same time – you’ll want to check out the inside info highlight below.


Let’s get right into it, shall we?


stamps all spread out


How Many Stamps Per Ounce are Needed for First Class Mail?


To send a standard letter via the United States Postal Service (through their First Class mail service) you’re going to need to attach either a Forever Stamp or a First Class mail stamp to that envelope.


A single Forever Stamp will cover the cost of First Class postage no matter what the current pricing is set at, which is the huge advantage of using these kinds of stamps compared to the more traditional “postage posted” stamps with their value printed on the face.


One of these stamps will allow you to send a 1 ounce letter through the mail via First Class delivery.


After that, though, figuring out how many stamps per ounce are needed to cover your First Class mail costs becomes a little bit trickier.


Let’s break down (almost) everything you need to know about calculating postage on those larger than 1 ounce envelopes!


calculating on a phone


Easy Rules for Calculating Postage


To kick things off, it’s important to understand that the number of stamps you are going to need to cover postage will depend on a variety of factors that include:


  • The type of envelope you are sending
  • The size of the envelope that you are sending and
  • The weight of the contents of that envelope


As we highlighted a moment ago, a Forever Stamp or a current First Class stamp is going to cover the postage for a single 1 ounce envelope to travel anywhere in the United States.


Sure, you’ll need a little bit of extra postage to get that same envelope to addresses overseas. And your postage costs will be unique depending on its ultimate destination around the world, but when mailing a letter to anyone in the United States that single stamp will usually cover all of your bases.


As soon as your letter starts to weigh more than a single ounce, though, you’re going to have to think about adding extra stamps to your envelope to avoid it being returned to sender for more postage.


As of 2021, the cost of each additional ounce of postage has jumped up to $0.20 per ounce.


This means that if you want to send a single ounce letter you’ll only have to attach one Forever Stamp and you are good to go. As soon as that letter tips the scales at 1.1 ounce (all the way up to 2.0 ounces) you’re looking at an extra $0.20 and postage that you have to cover.


This can be done in a couple of different ways.


To keep things simple, you can use a single Forever Stamp and then an additional $0.20 stamp (purchased from the post office) to cover the extra ounce of weight. These “fractional postage” stamps are available at every US Post Office and make it really easy to cover any fees that you weren’t expecting.


If, though, your envelope came in at 3 ounces you’d have to pony up $0.40 in extra postage fees – and that means purchasing a different fractional stamp (a $0.40 stamp) to cover your bases.


forever stamps


Using Forever Stamps to Cover First Class Postage


Some people like to streamline things even more so, though, and simply use Forever Stamps to cover all of their postage needs – even if it means that they sometimes “overpay” to get their letters sent to their intended recipients.


What are Forever Stamps?


Back in 2007, the United States Postal Service unveiled a new stamp program that they called the Forever Stamp program – changing the way that First Class postage was handled from that moment on.


Up until that point, postal customers had to purchase postage stamps that had been clearly marked with their total value and denomination somewhere on the face. When postage prices increased, however, those stamps became somewhat obsolete, requiring more postage stamps to be attached to make up the difference.


The USPS had to come up with fractional stamps to make up those pricing gaps and had been hunting for a solution to solve this problem once and for all.


With the Forever Stamps they created a system that guaranteed every Forever Stamp would be enough to cover First Class postage no matter what that postage price was at that particular point in time.


The stamps are 100% nondenominational and never expire, allowing postal customers to use one Forever Stamp that they might have purchased for $0.45 to cover First Class postage that may cost $0.55, $0.60, or $0.75 somewhere in the future!


The popularity of the Forever Stamp program compelled the USPS to all but eliminate the more traditional First Class stamp program in 2011.


Today, the overwhelming majority of stamps sold by the USPS are of the Forever Stamp variety.


In fact, if you want to purchase First Class stamps (denominational stamps) you have to order them in bulk quantities of at least 500 – placing a special order online or at your local post office!


Where Do I Buy Forever Stamps?


Forever Stamps are sold anywhere and everywhere that USPS stamps are available, including online, at your local post office, and at retail and department stores that offer postage options, too.


These are the stamps that you are almost always going to be given when you buy a book of stamps from the post office. The only way (highlighted above) to get traditional First Class stamps is to buy them in bulk quantities of 500 or more.


How Do I Use Forever Stamps?


You use Forever Stamps the same way that you would use First Class stamps, though now you don’t have to worry about “making up the difference” if you paid less for your Forever Stamps than what the current cost of First Class postage is today.


As an example, in 2007 when the Forever Stamp program was created the cost of First Class postage was pegged at $0.41 per stamp.


Today (the middle of 2021) the cost of First Class postage has climbed to $0.55 per stamp – but those Forever Stamps purchased back in 2007 are still eligible to cover the total cost of your mailing, even though there’s a $0.14 difference between when you bought them and what postage is today.


Since the cost of postage has almost always gone up over time (only dropping twice in 1919 and then in 2016) Forever Stamps are a bit of a good “investment” if you’re going to be sending a lot of letters through the mail and don’t want to keep paying higher and higher prices to cover the postage.


How Many Forever Stamps Per Ounce?


Where things get a little funky with Forever Stamps is when you have to add extra postage to your envelope to cover heavier items going through the mail.


As we mentioned earlier, the current (as of 2021) cost for each additional ounce of mail in a letter is at $0.20 per ounce while a Forever Stamp today costs $0.55.


The first Forever Stamp you attached to your envelope will cover the initial ounce, but then attaching a second Forever Stamp guarantees that you “overpay” for postage unless you are adding 2.5 extra ounces.


Most people don’t mind paying a little bit of extra by using Forever Stamps to cover their extra postage costs just because it simplifies the process so much. If you aren’t interested in that, though, you can still buy $0.20 stamps for each additional ounce of mail you stick into an envelope and attach it next to your Forever Stamp.


weighing mail


Weighing Your Mail to Figure Out Postage


The overwhelming majority of people aren’t going to spend a lot of time weighing out their envelopes, instead just assuming that pretty much anything that makes it into a standard sized envelope (measuring 11.5” x 5”) is going to be covered by a single stamp.


And while the odds are pretty good that most folks are going to be good to go, those that have to send a lot of paper in a single envelope (or are including something else in their letter) may have to actually weigh things out to figure new postage costs before they drop that letter in their mailbox.


A kitchen scale (especially one designed for baking) can provide you with all the information you need about how many stamps should be attached to an envelope to get it to its ultimate destination.


All you have to do is set a scale like that to read out weight in ounces, drop your envelope (filled out already) onto the scale, and then see if it’s more or less than a single ounce.


If it’s less than an ounce (or even just slightly over) the odds are pretty good you’ll be able to mail with a single Forever Stamp attached.


If it’s more than an ounce (we are talking any more than 1.25 ounces, really) the odds are pretty good you’re going to have to attach extra postage to get that letter through the mail into your intended recipient.


stamp with the US flag


How Many Stamps Will I Need for Larger Envelopes?


Believe it or not, you can actually use postage stamps to cover the costs of shipping larger envelopes – and even packages – if the cost isn’t going to be exorbitant.


For example, covering the cost of shipping a package that might run three dollars for First Class delivery can be done by attaching six Forever Stamps to the package and then dropping it off in the post or handing it off to a USPS employee at your post office.


Covering shipping costs that get up to $10 or more, however, is next to impossible to do with stamps alone. You’d have to cover almost an entire surface of your package in stamps – and that’s just not going to fly with the USPS these days.


Still, it’s kind of cool to know that in a pinch you could use up a stockpile of Forever Stamps to cover postage if you absolutely had to.


post office building


The Easiest Way to Know How Many Stamps You’ll Need


At the end of the day, the easiest way to know exactly how many stamps you’ll need to get a letter to its final destination is to visit the post office, hand the letter to them, and let them know how you’d like to have it sent.


They will weigh out the letter for you using their equipment, will be able to sell you the exact right amount of postage, and will even show you how to apply postage so that your letter is guaranteed to get to its ultimate destination just as quickly as humanly possible.


It really doesn’t get much better than that!


virtual mailbox on desktop


Effortlessly Manage Your Mailbox with US Global Mail


If you want to more easily manage your incoming mail, though, you’ll want to take a closer look at the services provided by US Global Mail through their virtual mailbox.


US Global Mail account holders get a permanent physical mailing address that better protects their privacy, a mailing address that they can have packages and letters sent to from any shipping service (including USPS, FedEx, UPS, DHL, and more).


On top of that, every single piece of mail that arrives at a virtual mailbox is immediately scanned and uploaded into your client dashboard. You’ll be able to see what has been delivered, and can even choose to have your mail digitally archived, too!


Combine all of that with free check depositing features, the ability to forward and route mail around the world at up to 80% off of traditional shipping costs, and all the other benefits that the virtual mailbox from US Global Mail provides and the service becomes a bit of a no-brainer.


For more info and details about this service, visit the US Global Mail website today!

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