How to check if a $100 bill is authentic
100-dollar bills are among the most counterfeited in the world, so it's important to know how to verify whether a bill is authentic or not. There are several methods you can use to identify a fake bill, and in this article we'll provide you with all the necessary information to do so.
What to look for on a 100-dollar bill
First of all, there are some features you should look for on a 100-dollar bill to determine whether it's authentic or not:
- Watermark: Every 100-dollar bill has a watermark to the left of the portrait on the front side of the bill. The watermark should be visible when holding the bill up to light.
- Safety strip: A vertical safety strip is embedded in the paper of the bill and is visible when holding the bill up to light. The strip contains the text "USA 100" and an image of Independence Hall's bell tower.
- Color-changing ink: The number "100" on the bottom right of the front side of the bill will change from copper to green when tilted.
- Tactile relief: On the bill, there are some raised parts, such as the text "The United States of America" and the number "100". These parts should be clearly distinguishable by touch.
These are just some of the safety signs you can look for on a 100-dollar bill. In the next paragraph, we'll provide you with more information about safety signs that can help you identify a fake bill.
Security features of 100-dollar bills
100-dollar bills are among the most counterfeited in the world, which is why the United States government has introduced numerous security features that make them difficult to counterfeit.
1. Watermark
The watermark is a thin, transparent design on the left side of the bill. When held up to light, you can see a miniature portrait of Benjamin Franklin (the president depicted on the bill).
2. Safety strip
The safety strip is embedded in the bill and is visible when held up to light. The strip contains repeated text "USA 100" and small star designs. If the bill is tilted, the designs on the strip appear to move up and down.
3. Color-changing ink
The color-changing ink used to print the number "100" on the back of the bill changes color from green to brown when the bill is tilted.
4. Microprinting
The bill has microscopic words that cannot be read with the naked eye but only with a magnifying glass. For example, above Franklin's hat, it says "The United States of America".
5. Tactile touch
The printing on an authentic bill has a slightly raised touch, especially on serial numbers and letters indicating the value of the bill.
- Note: These are just some of the security features present on the $100 bill. If you suspect you have a counterfeit bill, contact the appropriate authorities immediately.
How to Verify the Security Strip on the $100 Bill
The security strip is one of the primary security features present on the $100 bill. It is a vertical stripe that runs through the bill, visible from both sides. The strip contains miniature images of the Liberty Bell and the number "100". Here's how to verify if your $100 bill's security strip is authentic:
- Touch the strip: The security strip should be slightly raised to the touch.
- Hold up the bill to light: The security strip should appear continuous and unbroken. Additionally, the miniature images on the strip should be sharp and clear.
- Tilt the bill: Tilting the $100 bill should reveal a color-shifting effect. The images on the security strip become more prominent while the color of "USA" located at the bottom of the bill changes from green to black.
Remember to check all of its security elements, including paper, watermark, security thread, and left portrait when verifying an authentic $100 bill.
How to Verify the Security Thread on the $100 Bill
The security thread is one of the primary security features present in a $100 bill. It is a thin, long stripe vertically positioned on the left side of the bill, containing microprints of the bill's denomination.
To verify if the security thread is authentic, follow these steps:
- Hold the bill up to sunlight or a bright light source and observe the security thread closely. If it is authentic, you should see microprints of the denomination of the bill (e.g. "100" repeated multiple times) embedded within the thread itself.
- Touch the thread with your fingers to feel its texture. It should be slightly raised from the surface of the bill and have a rough texture to the touch.
- Tilt the bill so that the security thread is visible at different angles. If it is authentic, you will see that the color of the thread changes depending on the viewing angle. In particular, you will see a rainbow effect extending from top to bottom of the thread.
If you are unsure about the presence or authenticity of the security thread, compare it with an authentic $100 bill. This way, you can verify if its features match those of a genuine bill.
Remember that the security thread is just one of many security elements present in a $100 bill, so make sure to examine other details such as watermark, Portrait and Ink.
Other security features to verify the authenticity of $100 bills
In addition to the main security features described above, there are other functionalities that can help you determine whether a $100 bill is authentic or counterfeit.
1. Watermark
A watermark is a design embedded in the paper of the bill. If you hold the bill up to the light, you should see a slightly lighter shade of the portrait on the right. The watermark should be visible on both sides of the bill.
2. Security thread
A three-dimensional security thread is embedded in the $100 bill. If you tilt it, the "100" number on the thread should change color from copper to green.
3. Color-shifting ink
The ink used to print the "100" number on the front of the $100 bill will change color when the bill is tilted. The color will shift from green to black or from copper to dark green.
4. Microprinting
There are microprints on the $100 bill that are too small to be seen with the naked eye. If you use a magnifying glass, you should be able to see the words "The United States of America" written around Benjamin Franklin's collar and the "100" number on the front of the bill.
5. Serial number
Each $100 bill has a unique serial number consisting of two letters followed by eight digits. The serial numbers should match on both sides of the bill.
- Note: These security features are just some of the functionalities present on $100 bills. For more information, you can visit the website of the United States Department of Treasury.
Conclusion
Knowing how to verify whether a $100 bill is authentic is important to avoid falling victim to scammers trying to pass counterfeit bills. By using the security features described in this article, you can easily determine whether your bill is authentic or not. Always remember to check multiple features before accepting a $100 bill.
If in doubt, do not hesitate to contact the appropriate authorities for further verification.

Michael Anderson - Software Engineer
My name is Michael Anderson, and I work as a computer engineer in Midland, Texas.
My passion is sharing my knowledge in various areas, and my purpose is to make education accessible to everyone. I believe it is essential to explain complex concepts in a simple and interesting way.
With GlobalHowTo, I aim to motivate and enrich the minds of those who want to learn.





