Rates will be going up again. Letters will rise a penny to 50 cents. Your forever stamps will still be good.

Packages will see some increases. If you use electronic postage, the bottom rate for a first class package will go from $2.61 to to $2.66 ($3.50 if you go to the post office). As before, that rate will cover 1 through 4 ounces. Instead of a tier for the next 4 ounces, though, the rate will rise with each ounce beyond 4. Like last year, commercial mailers (electronic postage) will have a rate available for packages between 15 and 16 ounces. Those who go to the post office get kicked up to the priority mail rate.

Priority mail based on weight and zone is going up, generally (only a couple exceptions). Most flat rate boxes will rise 60 cents (medium flat rate will rise 45 cents).

Here's the blog posting from Stamps.com with charts and narratives. The blog (from a couple months ago) says the rates were subject to approval. It's my understanding they were approved.

http://blog.stamps.com/2017/10/26/usps-announces-2018-postage-rate-increase/