Collecting Signed Sports Cards: What to Know Before You Buy or Sell

Signed sports cards have become one of the most popular segments of the memorabilia market for the last 30 years. Whether pulled directly from a pack or signed in person by a player, these cards combine the nostalgia of collecting with the personal connection of an autograph. For Kansas City collectors, that can mean anything from a George Brett in person signed 1987 common to a Patrick Mahomes certified auto pulled from a Panini pack.

Patrick Mahomes II Rated Rookie autographed card, PSA/DNA certified Mint 9 — a Kansas City Chiefs collectible worth approximately $1,300.

Many newer cards come with autographs inserted directly into packs by the manufacturer. These are officially certified as authentic by the card company itself — often marked with a printed guarantee on the back or a hologram sticker. Certified autographs can range in value from as little as fifty cents to several thousand dollars depending on the player, rarity, and condition. For example, a limited-edition Mahomes rookie auto can bring in thousands, while a common bench player’s card might only be worth pocket change.

Former Kansas City Royals All-Star Ken Harvey autographed Leaf card — a certified auto directly from the card company.

Collectors also frequently obtain autographs in person — at ballparks, training camps, or through the mail. These vintage or modern cards aren’t certified by the manufacturer, so they sell as uncertified autographs. This market depends heavily on your ability to recognize authentic signatures. A good rule of thumb: if someone is offering a Patrick Mahomes signed card for $25 on eBay or at a garage sale, it’s almost certainly too good to be true - although a George Brett in person signed card might be real at a local Kansas City estate sale for $25. 

George Brett in-person signed 1988 Score card — a Kansas City Royals classic valued around $40 when unauthenticated.

For serious collectors, the most secure option is to buy or sell cards that have been authenticated and slabbed by a third-party grading company. PSA, Beckett (BGS), and CGC/JSA are the most respected names in the industry. A slabbed autograph card gives peace of mind that the signature has been examined and verified, which also makes it much easier to resell later — especially if the player’s value rises over time. In theory it would be great if you could authenticate all your in person signed cards, but the cost would be prohibitive as the fee for these services start at $25 per card and go up from their depending on the value. 

Bobby Witt Jr. 2020 Bowman Chrome Gold Shimmer autographed rookie card, PSA 10 Gem Mint — sold for $8,898 and rising.

At Sports Cleanout, we’re always looking to buy signed card collections — whether they’re pack-pulled certified autographs or in-person signatures. We know our autographs so no need to have them already authenticated. If you’re in the Kansas City area and have a collection to sell, reach out today to see what your autographed cards might be worth.

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📍 Based in Kansas City, Missouri—traveling throughout the Midwest