Most local USPS Post Offices sell pre-stamped postcards (stamped cards) and occasional sets of decorative postcards. You can also find a wider variety, including themed or commemorative sets, on the USPS online store .
Many Post Office branches sell postcards, particularly in tourist-heavy areas. Larger branches like the City of London Post Office are known to carry them alongside stamps and packaging. can you buy postcards at the post office
If you buy a plain postcard, you will need to purchase separate postage. Most local USPS Post Offices sell pre-stamped postcards
You can buy postcards and "maxicards" (postcards with a matching stamp pre-printed) at most Australia Post retail shops . including themed or commemorative sets
Most post offices in Canada offer postcards, often with the necessary stamps available at the same counter.