TX is the two-letter short form of the American state Texas. It is the official postal abbreviation, so you see it on addresses — 'Austin, TX 78701' — and on forms, maps, weather reports, sports tables and news headlines where space is tight. Every US state has one of these two-letter codes, always written in capitals with no full stops. TX is a written thing, not a spoken one: when reading an address aloud, people say 'Texas', not 'T X'. Because it is a fixed code, do not write 'Tx' or 'T.X.'. Be aware the same letters are used for other things in other worlds — in radio and telecoms TX means 'transmit' or 'transmitter', and in banking or crypto people write 'tx' for 'transaction' — but in an address, TX is Texas.