Do you need a stamp for first class mail

In the United States, the answer is: it depends on the weight and size of the mailpiece.

For First-Class Mail, you typically need a stamp for mailpieces that weigh 1 ounce or less and are not oversized. Here are some specific guidelines:

• For mailpieces that weigh 1 ounce or less and are not oversized, you can use a Forever Stamp, which is currently priced at $0.55.
• For mailpieces that weigh more than 1 ounce but not more than 2 ounces, you'll need to add additional postage. The cost is $0.15 per ounce, so a 2-ounce mailpiece would require a total of $1.10 in postage.
• For oversized mailpieces, such as those that exceed 11.5 inches in length, 6.125 inches in height, or 1/4 inch in thickness, you'll need to use a larger envelope or package and pay the applicable postage rate.

It's also worth noting that some mailpieces, such as those with extra services like tracking or insurance, may require additional postage.

To be sure, you can always check the USPS website or consult with a postal worker at your local post office for specific guidance on the postage requirements for your mailpiece.