One ounce. That's four sheets of typing paper plus the envelope.
Up to one ounce.
For First Class postage, one ounce using the Liberty Bell forever stamp, 44 cents.
it can weigh up to one ounce using one stamp
If you envelope weighs less than one ounce, it will take one forever stamp or one current first class stamp. If the letter and envelope weigh more than one ounce, the number of stamps will depend on the weight and the denomination of the stamps.
One regular 44-cent First Class stamp is all you need to send a letter anywhere inside the U.S. Additional postage is decided by the weight of the letter, not where it's coming from and going to. A regular First Class stamp covers all letters that weigh up to one ounce. Letters weighing more than one ounce will require additional postage. See the Related Link below for more details.
$00.72 Seventy two cents. All you have to do is buy a regular stamp from your post office and they will add the rest to it. Now, that is just a normal business sized envelope. They stamp it just like they stamp mail to the US. If your sending something heavier than that then they just weigh it and charge you just like they would for the US.
One 44-cent First Class stamp is all you need to mail a letter (weighing up to one ounce) anywhere within the United States. Postage is decided by the weight of the letter, not where it's coming from and going to. As long as the letter weighs one ounce or less, and is going to someplace within the U.S., it just needs one 44-cent stamp. If the letter does weigh over one ounce, then you can go to the post office and either have a teller take care of it, or use one of the automated machines (if they have one). The machine will weigh the letter and print out the postage for you, but I'm pretty sure the machines only take credit or debit cards (no cash).
One regular U.S. postage stamp (which currently cost 44 cents as of today, August 27, 2010) is all you need to mail a letter anywhere inside the U.S. Additional postage is decided by the weight of the letter, not where it's coming from and going to. One regular stamp is all you need for letters weighing up to one ounce. Letters over one ounce will require additional postage.
The amount of first-class postage is 42 cents anywhere in the U.S. How many stamps that is depends on the denomination of the stamps. If it's a 42-cent stamp, one will do.
It will cost $1.15 to send a letter out of the country by first-class mail for an international letter. There are stipulations on the envelope size, it must weigh one ounce or less, and not exceed $400 in value.
For plain letter sized paper, it should only be 1 stamp. The max weight for 1 stamp is 3.5 ounces, and a 4 page letter (plain paper) should not weigh anymore than 1 ounce.
First class letters are $0.46 per ounce. A 15 page letter will weigh around 2.4 ounces. Which means the letter will cost around $1.00 for extra postage.
At current rates $0.45 you get 1 ounce or 28.3495 grams before needing a second stamp which is an additional $0.20 for each ounce.