A friend of mine runs a small market booth and got hit with two counterfeit twenties in one week. I helped her shop for a detector and tested several at her register. Here are the five that I would trust to protect a cash register.
| Detector | Detection Method | Best For |
|---|---|---|
| Royal Sovereign RCD-3000 | UV, magnetic, IR | Small business counter |
| AccuBanker D63 | UV, magnetic | Compact countertop |
| Cassida 3300 | UV, magnetic, IR, size | Retail counter |
| Dri Mark Tri Test Pen | Iodine pen | Backup tool |
| Carnation CR2 | Full auto bill counter | High volume |
Royal Sovereign RCD-3000
This is the one I recommended to my friend. It does UV, magnetic ink, and infrared in one quick pass. The audible alarm and visual indicator make it impossible to miss a fake. It handles US, Canadian, and Euro bills, which mattered for her tourist-heavy market.
AccuBanker D63
The D63 is a compact UV and magnetic detector at a friendlier price. It is not as thorough as the RCD-3000 but for businesses that mostly handle twenties and below, it catches the majority of fakes. It runs on batteries which is handy for outdoor markets.
Cassida 3300
The Cassida 3300 adds size verification to UV, magnetic, and infrared tests. It catches bleached fakes where a small bill has been chemically stripped and reprinted as a larger denomination, which the size check immediately flags. Fast and reliable.
Dri Mark Tri Test Pen
The Tri Test Pen adds UV and magnetic tests to the classic iodine pen, all in one tool. I keep one in my own wallet as a backup. It is not a primary detector but it is cheap insurance when you are taking cash from a stranger at a flea market.
Carnation CR2
For high-volume businesses, the Carnation CR2 is a bill counter that also authenticates. Feed a stack of cash and it tells you the count, the total, and flags any suspect bills. It is overkill for a small booth but essential for restaurants or shops handling hundreds of bills a day.
What Matters Most
Multi-test detection is the only real defense. UV alone is fooled by good fakes. Magnetic ink testing catches most professional counterfeits because real bills have specific magnetic patterns in the ink. Infrared and size verification close the remaining gaps.
My Setup
For a single register, place the detector next to the cash drawer with a clear sight line. Train staff to check every bill of twenty dollars or more. The two seconds it takes is nothing compared to the loss of accepting a fake.
Common Mistakes
The biggest mistake is relying on the iodine pen alone. Bleached bills pass it and modern fakes use treated paper that does not react. The second mistake is only checking large bills. Counterfeit tens and twenties are common because people do not look as carefully.
Final Recommendation
For most small businesses, the Royal Sovereign RCD-3000 is my pick. For higher volume, step up to the Cassida 3300 or the Carnation CR2 counter. The Dri Mark pen is a fine backup but should not be your only line of defense.
Frequently asked questions
Do UV-only detectors actually work?+
UV catches most amateur counterfeits but misses professional fakes. For real protection you want multi-test detection including magnetic ink and infrared, especially for fifties and hundreds.
Are counterfeit pens enough?+
Pens only test for starch in the paper. Bleached real bills pass the pen test and modern fakes use the right paper. Pens are a last-resort tool, not primary protection.