Letters and postcards take about five days to reach the United States. That's airmail. It takes even longer in August, when postal staff is reduced; and during Christmas and Easter holidays. If what you're mailing is important, send it registered, which costs about €3.40 in Greece. For about €2.35 for a 20-gram envelope or postcard (with the cost increasing depending on the weight), you can send your letter "express"; this earns you a red sticker and faster local delivery. The ELTA post office also operates a courier service, EMS Express (otherwise known as ELTA courier). Delivery to the continental United States takes about two to four days, and costs €40. Packages take three to five days and cost depends on the weight. If you're planning on writing several letters, prepaid envelopes are convenient and cost €0.95 each.
Post offices are open weekdays 7:30–2, although in city centers they may stay open in the evenings and on weekends. The main post offices in Athens and Piraeus are open weekdays 7:30 am–8 pm, Saturday 7:30–2, and Sunday 9–1:30. The post offices at Athens International Airport and the Acropolis are open weekends, too. Throughout the country, mailboxes are yellow and sometimes divided into domestic and international containers; express boxes are red.
At this writing, airmail letters and postcards to destinations other than Europe and weighing up to 20 grams cost €0.90, and €1.45 for 50 grams (€0.90 and €1.30, respectively, to other European countries, including the United Kingdom).
Hellenic Post (ELTA). 800/118–2000; 210/335–3777; www.elta.gr.