Postage rates went up on Sunday, but it probably won't affect your regular mail. The basic 44-cent stamp will remain the same, but if your envelope is heavier than one ounce, you will pay an additional 20 cents, up from 17 cents. For magazines or promotional flyers, that rate is increasing, says an AP report. Post card rates are also rising to 29 cents. According to the report - the Post Office lost about $8.5 billion last year and the rate increases, estimated to bring in about $340-million this fiscal year, won't make much of a dent in that. But the agency is restricted to increases lower than the rate of inflation.