The 2009-S Guam Quarter is worth anywhere from $1.50 in circulated condition to over $15 or more in pristine proof grades — and some rare errors can push that value even higher. If you found one in your change jar or inherited a collection, you’re in the right place to find out exactly what it’s worth.
What Is the 2009-S Guam Quarter?
The 2009-S Guam Quarter is part of the U.S. Mint’s DC and U.S. Territories Quarter Program, which honored six territories and the District of Columbia in 2009. Guam was one of those featured territories, and the “S” mint mark on the coin means it was struck at the San Francisco Mint — which produced proof and silver proof versions, not coins for everyday circulation.
That distinction matters a lot for value. Proof coins are specially made with polished dies and blanks to create a sharp, mirror-like finish. Most people who find an S-mint coin in an old collection or gift set have something worth holding onto.
If you’re not sure what mint mark you’re looking at or need help identifying the coin quickly, a free coin identifier app can scan your coin and pull up details in seconds — no coin expertise required.
How Much Is the 2009-S Guam Quarter Actually Worth?
The value of a 2009-S Guam Quarter depends on which version you have. There are two main types: the standard clad proof and the silver proof. Both carry a premium over face value, but the silver version is worth significantly more.
Here’s a quick breakdown of what collectors typically pay:
| Version | Condition | Estimated Value |
|---|---|---|
| Clad Proof (S) | PR65 | $2 – $5 |
| Clad Proof (S) | PR69 Deep Cameo | $8 – $15 |
| Silver Proof (S) | PR65 | $8 – $12 |
| Silver Proof (S) | PR69 Deep Cameo | $15 – $30+ |
| Error Coin | Varies | $50 – $200+ |
For a deeper look at how these numbers compare to other 2009 quarters, check out this detailed guide on 2009 quarter values across all five territory designs — it’s a great resource for understanding the full picture.
How to Tell If You Have the Silver Version
The silver proof 2009-S Guam Quarter contains 90% silver, making it more valuable both to coin collectors and to silver stackers. The easiest way to tell the difference at home is to check the coin’s edge.
A clad coin will show a copper-colored stripe along the edge. A silver proof will have a completely uniform, silver-white edge with no copper visible at all. If you’re still unsure, CoinKnow can help you identify the composition and grade of your coin instantly — it’s one of the most reliable tools available for everyday collectors.
You can also look for the original packaging. Silver proofs were sold in special U.S. Mint sets and come in protective plastic with a certificate of authenticity. If your coin is still sealed in its original mint packaging, that’s a great sign you have the silver version.
Are There Any Valuable Error Coins to Watch For?
Error coins are where the real excitement can happen. The 2009-S Guam Quarter, like other Washington quarters from this era, occasionally shows up with minting errors that dramatically increase its value.
Some of the most notable errors to look for include:
Double die obverse — where Washington’s portrait or the date appears doubled or slightly blurred. These can be worth $50 to $150 depending on how visible the doubling is.
Off-center strikes — where the design is noticeably off-center on the blank planchet. Dramatic off-center examples (20% or more) can bring $100 or more at auction.
Die cap errors and clipped planchets are rarer but have sold for several hundred dollars when verified. Use CoinKnow to scan your coin for any unusual features before assuming it’s ordinary.
Tips for Selling or Grading Your 2009-S Guam Quarter
If you believe your 2009-S Guam Quarter is in top condition or might have an error, getting it professionally graded is worth considering. Services like PCGS and NGC grade and encapsulate coins, which can significantly increase resale value and buyer confidence.
For most people with a standard proof example still in its mint set, the easiest option is to sell through eBay, a local coin show, or an estate dealer. Expect to get somewhere between $3 and $20 for a nice proof example, depending on the grade and whether it’s clad or silver.
If you want to check current market prices before selling, CoinKnow gives you real-time value estimates based on recent sales data — which is far more reliable than guessing from an outdated price guide.
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FAQ
Q: Is the 2009-S Guam Quarter rare?
A: It’s not rare in terms of mintage — the U.S. Mint produced millions — but it’s not a circulation coin, so finding one in everyday change is unusual. Its value comes primarily from being a proof or silver proof issue.
Q: Can I find a 2009-S Guam Quarter in circulation?
A: Technically no. The “S” mint mark means it was made exclusively for collectors as part of proof sets. If you found one loose, it likely came from a broken-up proof set.
Q: How do I know if my Guam Quarter has an error?
A: Look closely at the design under good lighting or a magnifying glass. Signs include doubled images, off-center designs, or unusual edge characteristics. A coin identification app or professional grader can give you a definitive answer.
