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The 1988-S Washington Quarter is worth anywhere from $3 in typical proof condition to over $500 for perfect specimens with rare certifications. While you won’t find this specific “S” mint mark coin in your pocket change today, it remains an affordable favorite for many American families starting a collection.
| Condition / Grade | Estimated Value |
|---|---|
| PR65 (Deep Cameo) | $3.00 – $5.00 |
| PR69 (Deep Cameo) | $12.00 – $18.00 |
| PR70 (Deep Cameo) | $150.00 – $550.00 |
Understanding the 1988-S Washington Quarter
If you have discovered a 1988 quarter featuring a small “S” letter next to Washington’s ponytail, you have found a Proof coin. Unlike the millions of quarters struck in Philadelphia and Denver for everyday spending, the San Francisco Mint produced these coins specifically for collectors. To ensure you are accurately identifying your find, using a top coin identifier app can help distinguish between standard circulated strikes and these high-mirror proof versions.
Proof coins like the 1988-S were struck using specially polished dies and planchets (coin blanks). This process results in a stunning contrast where the portrait of George Washington appears “frosted” or matte, while the background field is as reflective as a mirror. Because they were sold in protective plastic sets by the U.S. Mint, finding one today usually means a collector set was “broken up” or inherited.
By using the CoinKnow app, you can quickly scan your coin to see if it retains its original Deep Cameo (DCAM) finish. A Deep Cameo designation is vital for the 1988-S Washington Quarter value, as any scratches or fingerprints on the mirrored surface will significantly lower the market price.
Your Old Coin Could Be Valuable!
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Comparing 1988-S Mint Marks and Mintage Figures
The 1988-S Washington Quarter is part of a larger production year that saw billions of quarters enter the American economy. However, the “S” version is much scarcer than its “P” and “D” counterparts. While Philadelphia and Denver produced nearly 1.2 billion quarters combined for circulation, the San Francisco Mint struck only about 3.2 million proof quarters.
Your Old Coin Could Be Valuable!
Identify It & Know Its Real Value — Free Download
While 3.2 million might sound like a large number, it is quite small in the world of numismatics. Most of these coins are tucked away in “1988 Proof Sets.” If you find an individual 1988-S in a bin or a plastic flip, it has likely been handled. Investors and collectors often look for the 1988 Washington quarter auction records to see how the S-mint compares to the rare high-grade business strikes from Philadelphia.
| Mint Mark | Coin Type | Mintage |
|---|---|---|
| P (Philadelphia) | Circulation Strike | 562,052,000 |
| D (Denver) | Circulation Strike | 596,810,688 |
| S (San Francisco) | Proof Strike | 3,262,948 |
Identifying Grades and the PR70 Price Jump
The value of your 1988-S quarter depends almost entirely on its grade. Professional grading services like PCGS or NGC use a 70-point scale. For proof coins, the grade is preceded by “PR” (Proof). A 1988-S in PR65 or PR67 condition is very common and typically sells for approximately $5.
Your Old Coin Could Be Valuable!
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However, once you reach the “perfect” grade of PR70, the 1988-S Washington Quarter value increases significantly due to registry set competition. Collectors who want the best possible version of every year will pay a premium for a coin that shows no flaws even under 5x magnification.
If you suspect your coin is flawless, CoinKnow can provide high-resolution comparison photos to help you decide if it’s worth the fee to have it professionally graded. Usually, unless the coin is in a sealed mint case and looks absolutely pristine, it will likely fall into the PR68-PR69 range.
Common Errors and Varieties for 1988 Quarters
While the 1988-S is a proof coin—meaning the Mint took extra care during production—errors can still occur. Error collectors look for “Doubled Dies,” where the letters or numbers appear to have a shadow or second image. On a 1988-S, this is extremely rare but would drive the value into the hundreds of dollars.
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More common in 1988 were “Clad Layer Errors” or “Off-center Strikes,” though these are almost exclusively found on the P and D mint marks. If you find a 1988-S that looks “off,” check for “die polish lines” or “milk spots.” While not errors, these imperfections can actually decrease the value of the coin below its bullion or face value.
| Potential Feature | Effect on Value |
|---|---|
| Deep Cameo Contrast | Highly Desirable (+Value) |
| Hazing / Milk Spots | Negative Impact (-Value) |
| Doubled Die Obverse | Very Valuable (Rare) |
Is the 1988-S Silver or Nickel?
A common misconception among everyday Americans is that all proof coins are made of silver. For the year 1988, the San Francisco Mint only produced “Clad” quarters for the standard proof sets. This means the 1988-S Washington Quarter is made of a core of pure copper with an outer layer of 75% copper and 25% nickel.
You can verify this by looking at the edge of the coin. If you see a distinct copper-colored stripe running along the edge (the “reeds”), it is a clad coin. Silver quarters were not reintroduced to proof sets until 1992. Therefore, your 1988-S doesn’t have “melt value” from precious metals; its value is strictly based on its collectibility and condition.
Your Old Coin Could Be Valuable!
Identify It & Know Its Real Value — Free Download
Because there is no silver content, the CoinKnow app’s real-time market data is the best way to track pricing fluctuations, as these coins rely on the hobbyist market rather than the global silver spot price.
Where to Sell Your 1988-S Washington Quarter
If you’ve determined that your quarter is in excellent condition, you might be wondering where to cash in. For coins valued under $15 (most 1988-S proofs), eBay is the most common marketplace. Selling them as individual coins or as part of a “Year Set” can attract hobbyists looking to fill holes in their albums.
For those rare PR70 Deep Cameo specimens, major auction houses like Heritage Auctions or GreatCollections are better venues. These platforms cater to serious investors who are willing to pay the top-tier prices we mentioned earlier. Always remember to factor in shipping and grading costs before deciding to sell a low-value coin.
FAQs
Q: Why is my 1988 quarter shiny but has no “S” mint mark?
A: If it has no mint mark or a “P”, it was made in Philadelphia. If it’s very shiny, it might be a “proof-like” uncirculated coin or simply a well-preserved business strike. These are worth roughly face value ($0.25) unless in perfect condition.
Your Old Coin Could Be Valuable!
Identify It & Know Its Real Value — Free Download
Q: Can I find a 1988-S in my change?
A: It is rare but possible. These are called “Impaired Proofs.” Because they have been circulated, they lose their mirror finish and are generally only worth 25 cents to $1.
Q: What is the most ever paid for a 1988-S Quarter?
A: In recent years, perfect PR70 Deep Cameo examples have sold at auction for over $500, though the average “perfect” coin typically sells for between $150 and $200 depending on the grading company.
Q: How should I store my 1988-S proof coin?
A: To preserve its value, avoid touching the surface with your fingers. Oils from skin can cause permanent damage. Keep it in a PVC-free plastic flip or a specialized coin album.