7 Expert Tips To Verify If A 100 Bill Is Genuine And Avoid Counterfeits

In an age where digital payments dominate, cash still plays a vital role—especially for high-value transactions. The $100 bill remains one of the most widely circulated U.S. banknotes globally, making it a prime target for counterfeiters. According to the U.S. Secret Service, millions of counterfeit dollars are seized annually, with fake $100 bills accounting for a significant portion. Whether you're a small business owner, traveler, or simply receiving change, knowing how to spot a fake $100 bill is essential. These seven expert-backed techniques will help you quickly and confidently identify authenticity using simple tools: your eyes, hands, and common sense.

1. Check the Color-Shifting Ink

One of the most distinctive security features on modern $100 bills is the color-shifting ink used in the lower right corner on the front. This ink changes color when you tilt the bill. Genuine notes display a number \"100\" that shifts from copper to green as the angle changes.

Fake bills often fail to replicate this effect accurately. Counterfeit versions may show no shift at all, a weak transition, or even use glitter or foil stickers to mimic the feature—both of which feel different to the touch.

Tip: Always tilt the bill under a light source to observe the full color transition. Don't rely solely on static observation.

2. Examine the 3D Security Ribbon

Introduced in the 2013 redesign of the $100 bill, the blue 3D security ribbon is woven into the fabric of the note—not printed on top. When you move the bill, the images of bells and 100s appear to move and shift in front of and behind the background stripes.

This motion illusion is created through micro-lenses embedded in the ribbon and cannot be duplicated by standard printers. On counterfeit bills, the ribbon is often flat, printed, or glued on, lacking dynamic movement.

Feature	Genuine Bill Behavior	Counterfeit Red Flag
3D Ribbon Movement	Bells turn into 100s as bill tilts	No movement; image is static
Ribbon Texture	Smooth, integrated into paper	Sticky, raised, or peeling at edges
Color Accuracy	Vibrant blue with depth	Dull, faded, or uneven coloring

3. Feel the Raised Printing

The portrait of Benjamin Franklin and other key elements on the front of the bill are produced using intaglio printing, a process that leaves ink slightly raised above the surface. Running your fingertip across his shoulder or collar should reveal a crisp, textured feel.

Most counterfeit bills are made using offset printing, which produces a flat, smooth image. If the entire surface feels uniformly slick—even under magnification—the note is likely fake.

“Tactile verification is one of the fastest ways to detect counterfeit currency. The raised print is hard to duplicate without specialized equipment.” — Agent Marcus Tran, U.S. Secret Service (ret.)

4. Hold It Up to the Light: Look for the Watermark and Security Thread

When held up to a bright light, two hidden features become visible:

• Watermark: A faint image of Benjamin Franklin appears on the right side of the bill, visible from both sides. It’s not printed—it’s formed during the papermaking process.
• Security Thread: A vertical strip running to the left of Franklin glows pink under ultraviolet (UV) light. It’s embedded in the paper and reads “USA 100” in alternating directions.

Counterfeiters sometimes print fake watermarks or add external threads, but these lack depth and alignment. A genuine watermark aligns perfectly with the portrait and doesn’t smudge or smear.

Tip: Use a UV flashlight (available inexpensively online) to verify the glow of the security thread. Many counterfeit detection pens fail on real new bills—UV testing is more reliable.

5. Inspect Microprinting and Fine Detailing

Zoom in—literally. Using a magnifying glass or smartphone macro lens, examine the following areas:

1. The quill pen near Franklin’s shoulder contains microprinting of “THE UNITED STATES OF AMERICA,” too small to be replicated clearly by most printers.
2. The Federal Reserve seal and serial numbers should have sharp, consistent edges.
3. The intricate scrollwork around the borders remains crisp on real bills but blurs or pixelates on fakes.

If text appears fuzzy, broken, or blocky under magnification, the bill is suspect. High-resolution scanners and consumer printers still struggle to reproduce such fine detail without distortion.

6. Verify Serial Numbers and Alignment

Every authentic $100 bill has two unique serial numbers—one on each side. These numbers must match exactly in font, size, color, and alignment. Here’s what to check:

• Consistency: Both numbers should be identical.
• Font: Uses a specific Helvetica-like typeface with uniform spacing.
• Alignment: Perfectly aligned with surrounding design elements.
• Sequence: No repeated digits in patterns (e.g., 11111111), which suggest random generation.

A mismatched or misaligned serial number is a major red flag. Some counterfeiters copy only one side and duplicate it, leading to identical front-and-back serials—which never happens on real currency.

7. Trust the Paper Quality

U.S. currency isn’t printed on regular paper. It’s made from a blend of cotton and linen with durability and texture designed to last. Real bills feel crisp, firm, and slightly rough—not flimsy or overly glossy.

Additionally, genuine bills do not fluoresce (glow) under UV light—except for the security thread. If the entire bill glows blue or white, it’s likely made from standard wood-pulp paper, a hallmark of counterfeits.

“The paper itself is a first-line defense. No amount of ink can disguise the wrong substrate.” — Dr. Lena Pruitt, Currency Forensics Analyst, Bureau of Engraving and Printing

Mini Case Study: How a Coffee Shop Owner Avoided $1,200 in Losses

Sophia Ruiz runs a busy café in Miami where large bills are common. One evening, a customer paid with three $100 bills for a $45 order. Something felt off. She remembered seeing a training video about the 3D ribbon. Tilted slowly, two of the bills showed no movement. She politely asked for another form of payment, citing policy. Later, she reported the bills to local authorities. The U.S. Secret Service confirmed they were part of a regional counterfeit ring using high-quality color printers but failing to replicate motion-based security features. Sophia avoided losing over $200 in cash and potential legal complications from unknowingly passing fake bills.

Step-by-Step Verification Checklist

Use this quick-reference guide anytime you receive a $100 bill:

1. Tilt the bill: Observe the color shift from copper to green in the lower right.
2. Check the blue ribbon: Tilt side to side—bells should transform into 100s.
3. Feel the texture: Run your finger over Franklin’s collar for raised printing.
4. Hold to light: Confirm the watermark and vertical security thread.
5. Use UV light: Ensure only the thread glows pink—not the paper.
6. Inspect microprint: Look for clear, unbroken tiny text near the quill.
7. Compare serials: Verify matching numbers, fonts, and alignment.

Frequently Asked Questions

What should I do if I receive a counterfeit bill?

Do not return it to the person who gave it to you. Note details like appearance and vehicle description if possible. Contact your local police or the U.S. Secret Service immediately. Submit a report via the Secret Service online portal. You are responsible for surrendering the bill—banks will not reimburse counterfeit currency.

Can counterfeit detection pens reliably identify fake $100 bills?

Not always. These pens react to starch in wood-based paper, turning dark. However, many modern counterfeits use low-starch or specialty paper, yielding false negatives. Additionally, some genuine older bills may contain trace starch and react incorrectly. Pens are useful as a preliminary tool but should never replace physical inspection of security features.

Are older $100 bills without the blue ribbon still valid?

Yes. Bills issued before 2009 (with the large portrait) are still legal tender, though less common. They lack the 3D ribbon and color-shifting ink but include watermarks, security threads, and microprinting. Be extra cautious with older designs, as they’re easier to forge.

Final Thoughts: Stay Alert, Stay Protected

Verifying a $100 bill doesn’t require advanced technology—just attention to detail and familiarity with its built-in defenses. As counterfeit techniques evolve, so must our vigilance. By mastering these seven methods, you protect not only your finances but also the integrity of everyday commerce. Whether you're handling cash at work or accepting payment from a stranger, take those few extra seconds to inspect. That small effort could save you hundreds—or prevent a criminal from profiting.

💬 Have you ever encountered a counterfeit bill? Share your experience or verification tip in the comments to help others stay alert.