First Class Mail
Advantages: Quick Delivery: First Class mail, in-state, is generally delivered in 1 to 3 days, and usually takes less than a week to reach anywhere in the continental U.S.
Returned Mail: Bad addresses and moves that are 12 to 18 months old come back to the sender at no charge. Moves within 12 months automatically get forwarded (or could be directed by the use of postal endorsements) to come back to the sender. In either case, there is no charge.
Disadvantages: Cost: First Class mail costs more than some of the other mailing options.
Weight / Cost: The cost of first class mail rises incrementally with every ounce.
Weight Restriction: First Class mail cannot exceed 13 ounces.
Standard Mail (Bulk Rate)
Advantages: Low Cost: The Post Office gives standard mail users a low postage rate.
Up to 3.3 ounces: You pay the same rate up to 3.3 ounces. Beyond 3.3 ounces it incrementally increases to a maximum of 16 ounces.
Incremental postage increase: After 3.3 ounces, postage goes up incrementally as the weight goes up.
Disadvantages: Slow Delivery: Standard mail generally takes 4 to 13 business days, in-state. You can expect to wait 10 days up to 3 weeks for mail going across the country.
Return mail is not free: Any bad addresses that are more than 12 months old are either not returned or you have to pay a fee.
Weight Restriction: Weight of a single piece cannot exceed 1 pound.
Qualification: Standard mail must be either 200 pieces or have a combined weight of 50