The short answer
Old postcards deserve a look before anything else. Sort them into piles, read the messages and postmarks for clues about the sender and the date, then check whether any are genuinely valuable. From there the path is yours: keep the best for a collection, display a few, store the rest properly, sell the duplicates, or pass the ones with blank backs to a new sender. The wrong move is doing nothing until they sit in a drawer for another generation.
First: sort everything
Spread the cards on a table and group them — by place, by sender, by era, or simply by whether the back is written on. Sorting forces you to look at each card once, and looking is where the discoveries start: a town you know, a family name, a postmark from a date that matters.
If the cards came from a relative, they may be family history as much as postcard history. Read them before you decide anything. The how to date a postcard guide helps you place each card in time from its style, stamp, and message.
Then: check for value
Most old postcards are worth a little; a few are worth a lot. Value comes from the subject, the publisher, the condition, and whether the card is a real photo or an early divided-back rarity. The are old postcards worth anything guide covers the honest basics, and the vintage style vs vintage postcards guide explains why a modern reproduction is not the same as a genuine old card.
Keep the keepers — start or feed a collection
Once you know what you have, keeping the best is easy. A collection can be as small as a shoebox of hometown views or as focused as every card of one state's coast. The how to start a postcard collection guide is written for exactly this moment.
Display the favorites
A handful of old postcards can become a small gallery: framed on a wall, pinned to a board, or standing in a tabletop frame. Keep them out of direct sunlight and away from damp walls. For the practical side of showing them off, see how to display postcards.
Store the rest properly
Cards you are not displaying still need care: keep them flat, away from light, heat, and humidity, in acid-free sleeves or albums rather than sticky pages. Do not trim, tape, or write on them, and leave old stamps in place — they are part of the card's history. The full routine is in how to store and preserve postcards.
Sell or pass along what you do not need
Duplicate views and cards outside your interest are the ones to sell or give away. Collectors buy old postcards by subject and place, so a clear description of the scene and the postmark helps. For cards with blank backs and nothing written on them, one more option fits the atlas: send a piece of home with Postcrossing and let an old view travel again.
Why old postcards matter
Every old card is a small record of a place at one moment — a Main Street before the cars, a shoreline before the marina, a hotel that is gone now. That is why museums and libraries collect them, and why the history of the postcard is really the history of how places saw themselves. Whatever you decide to do with a box of them, you are holding something worth a second look.