A bank note is a piece of physical paper currency issued by a country’s central bank, carrying the face value printed on it because the government declares it legal money and the public treats it that way. In the United States, every paper bill is a Federal Reserve Note, produced for as little as 7 cents yet spending at full face value entirely because federal law says it does. That gap between what a bill costs to make and what it buys is the whole mechanic of modern cash, and it explains the rules around when someone has to accept your money, what counts as counterfeit, and what to do with a bill the dog ate.
What a Bank Note Is
At its legal root, a bank note is a type of promissory note: an unconditional written promise to pay the bearer a specified amount. Historically that promise was literal. You could walk into a bank and exchange the note for a set weight of gold or silver. The United States abandoned that commodity link in stages during the twentieth century, and today’s Federal Reserve Notes are purely fiat currency. Their value comes from the government’s declaration that they are money and from the shared willingness of everyone in the economy to treat them that way.
A $20 bill costs the government roughly 7.3 cents to print, covering the specialized paper, ink, and labor.1Board of Governors of the Federal Reserve System. How Much Does It Cost to Produce Currency and Coin? The remaining $19.93 of value exists because the law says it does and because every store, bank, and person in the country agrees.
On the Federal Reserve’s own books, every note in circulation is a liability. Federal Reserve Notes are the largest category of liabilities on the central bank’s balance sheet.2Board of Governors of the Federal Reserve System. Federal Reserve Liabilities In practice, a note is a non-interest-bearing claim against the Fed with no maturity date. The only thing the government promises is that you can exchange one denomination for equivalent denominations — five $20 bills for a $100, say. No gold, no silver, no redemption for anything other than more of the same legal tender.
Who Issues U.S. Bank Notes
The Federal Reserve System controls the issuance of all U.S. bank notes. The Federal Reserve Act authorizes the Board of Governors to issue Federal Reserve Notes, which the law designates as “obligations of the United States.”3Board of Governors of the Federal Reserve System. Federal Reserve Act Section 16 – Note Issues The physical printing happens at the Bureau of Engraving and Printing, which operates under the Department of the Treasury and has been producing currency since 1862.4Bureau of Engraving and Printing. The Buck Starts Here: How Money is Made
Seven denominations are currently produced: $1, $2, $5, $10, $20, $50, and $100. Larger denominations like the $500 and $1,000 were last printed decades ago but remain legal tender. Any design of U.S. currency ever issued is still valid if you happen to hold one.5U.S. Currency Education Program. The Seven Denominations In practice, those old large-denomination notes are worth far more to collectors than their face value.
When Someone Has to Accept Your Cash
Federal law states that U.S. coins and currency, including Federal Reserve Notes, “are legal tender for all debts, public charges, taxes, and dues.”6Office of the Law Revision Counsel. 31 USC 5103 Legal Tender If you owe someone money — a loan payment, a court judgment, a tax bill — they cannot refuse payment in cash. Tendering the full amount in legal currency satisfies the debt as a matter of law, even if the creditor would have preferred a check or a wire.
Here’s the part that surprises most people. Legal tender status does not force a business to take your cash for a new purchase. No federal statute requires a private business to accept paper currency for goods or services.7Board of Governors of the Federal Reserve System. Is It Legal for a Business in the United States to Refuse Cash as a Form of Payment? A coffee shop with a “card only” sign is perfectly legal under federal law, because you have no pre-existing debt when you walk up to the counter. The obligation hasn’t been created yet, so the legal tender rule doesn’t kick in. Several states and cities have passed their own laws requiring businesses to accept cash, but the federal rule draws a hard line between settling a debt and making a new purchase.
How to Tell a Real Bill from a Fake
U.S. currency is printed on a distinctive blend of 75% cotton and 25% linen, manufactured exclusively for the Bureau of Engraving and Printing. Tiny red and blue synthetic fibers are distributed randomly throughout the paper, and possessing this substrate is illegal for anyone other than the BEP.4Bureau of Engraving and Printing. The Buck Starts Here: How Money is Made Counterfeits printed on standard paper feel different immediately to anyone who handles cash regularly.
Beyond the paper itself, each denomination carries layered security features designed so that anyone can verify authenticity quickly:
- A security thread runs vertically through every genuine note from the $5 up, inscribed with the denomination and visible when held to light. Each denomination’s thread sits in a different position and glows a different color under ultraviolet light.8United States Secret Service. Know Your Money
- A watermark, usually matching the portrait on the bill, becomes visible when the note is held to light. Like the security thread, it’s embedded in the paper during manufacturing rather than printed on the surface.
- On $10, $20, $50, and $100 bills, color-shifting ink in the numeral at the lower right corner shifts from copper to green when tilted.8United States Secret Service. Know Your Money
- The $100 bill has a 3-D Security Ribbon, a blue strip woven into the paper that displays bells and the number 100 shifting as you tilt the note. Because it’s woven rather than printed, standard printers can’t reproduce it.
- Microprinting places tiny text in various spots on the note. Photocopiers and consumer printers can’t reproduce text that small with any clarity.
These features work in combination. A convincing counterfeit might replicate one or two, but reproducing all of them on the correct substrate is extraordinarily difficult. Holding a bill to light to check the watermark and security thread catches most fakes in seconds.
What Happens If You End Up with a Counterfeit
Manufacturing counterfeit U.S. currency is a federal crime punishable by up to 20 years in prison, a fine, or both.9Office of the Law Revision Counsel. 18 USC 471 Obligations or Securities of United States The same maximum penalty applies to anyone who knowingly passes, possesses, or conceals counterfeit currency with intent to defraud.10Office of the Law Revision Counsel. 18 USC 472 – Uttering Counterfeit Obligations or Securities That second provision matters more than people realize. Knowingly trying to spend a fake $50 bill carries the same potential sentence as printing it.
If you discover or suspect a counterfeit bill in your possession, the Secret Service instructs you to submit it to your local police department, which forwards it for investigation. Banks and cash processors follow the same chain, ultimately routing suspected notes to the Secret Service.11United States Secret Service. Counterfeit Investigations One detail catches people off guard: you will not be reimbursed. If you unknowingly accepted a counterfeit bill and it gets identified later, the loss falls on you. The government does not compensate businesses or individuals for confiscated counterfeits, which is a strong practical reason to check bills when you receive them.
What to Do with Damaged Bills
Notes go through the wash, survive house fires, or get chewed up by a pet. When a bill is too damaged for a bank to process normally, the Bureau of Engraving and Printing operates a free redemption service for mutilated currency. The BEP defines “mutilated” currency as a note where half or less of the original remains, or where the damage is severe enough that the value is questionable.12Bureau of Engraving & Printing. Mutilated Currency Redemption
The rules are straightforward. If clearly more than 50% of a note remains along with identifiable security features, the BEP pays full face value. If 50% or less remains, the BEP will still pay full value, but only if the evidence shows the missing portion was completely destroyed, for example in a documented fire.12Bureau of Engraving & Printing. Mutilated Currency Redemption Send in half a bill without proof the other half was destroyed, and the BEP will refuse the claim. That rule exists for an obvious reason: without it, someone could tear a note in half and submit each piece for double the face value.
When Cash Triggers Paperwork
Using large amounts of physical cash triggers federal reporting obligations that don’t apply to checks or electronic transfers. Any business that receives more than $10,000 in cash from a single transaction, or from two or more related transactions, must file IRS Form 8300.13Internal Revenue Service. About Form 8300, Report of Cash Payments Over $10,000 Received in a Trade or Business This applies to car dealers, jewelers, real estate agents, and essentially any business involved in a high-value cash sale.
The same $10,000 threshold applies at banks and financial institutions, which file separate Currency Transaction Reports for large cash deposits or withdrawals. Deliberately breaking a transaction into smaller amounts to avoid these reporting thresholds, known as structuring, is itself a federal crime, even if the underlying money is completely legitimate. If you are making a large cash purchase or deposit, the practical advice is simple: complete the transaction normally and let the business or bank file whatever reports the law requires.