How Long Does a Patent Last? (Utility, Design & Maintenance)

A utility patent lasts 20 years from its earliest filing date. A design patent lasts 15 years from the date it's granted. Those are the headline numbers, but the details—especially the "from filing, not grant" part—decide how much protection you actually get.

The Two Main Answers

Patent type	Term length	Clock starts at	Maintenance fees?
Utility (how something works)	20 years	Earliest non-provisional (or PCT) filing date	Yes
Design (how something looks)	15 years	Grant date	No

Most patents people care about are utility patents—the kind that protect a machine, process, chemical, or software method. Design patents protect the ornamental appearance of a product, like the shape of a bottle or the layout of an app icon.

Why "From Filing, Not Grant" Matters

A utility patent's 20-year clock starts ticking the day you file your application—not the day the patent is granted (35 U.S.C. §154). That distinction has real consequences.

Examination at the USPTO often takes two to three years, sometimes longer. Every month your application sits in the queue is a month subtracted from your eventual monopoly. File in 2026, get granted in 2029, and you've already burned three years of your 20 before you can enforce anything. Your patent would expire in 2046, not 2049.

This is the opposite of how many people assume patents work. They picture the clock starting when the certificate arrives. It doesn't. Slow prosecution quietly shrinks the life of your patent—which is one reason applicants and attorneys care about moving an application along efficiently.

One helpful wrinkle: if you started with a provisional application, its 12-month pendency does not count against your term. The 20 years runs from your non-provisional filing date. A provisional buys you a year of "patent pending" status and an early priority date without spending any of your eventual 20 years.

Maintenance Fees: Pay or Lose It

A granted utility patent isn't a "set it and forget it" asset. To keep it alive for the full 20 years, you have to pay maintenance fees at three checkpoints after grant. Miss one, and the patent expires early and drops into the public domain—free for anyone to use.

Here's the schedule, with large-entity amounts:

Deadline (after grant)	Large entity	Small entity (40%)	Micro entity (20%)
3.5 years	$2,150	$860	$430
7.5 years	$4,040	$1,616	$808
11.5 years	$8,280	$3,312	$1,656

A few things to notice. The fees escalate sharply—the final payment is nearly four times the first. That's intentional. The system nudges owners to abandon patents they no longer value, returning those inventions to the public sooner. Many patents are deliberately allowed to lapse at the 7.5- or 11.5-year mark because they're no longer worth the money.

Note also that small and micro entities pay reduced rates—40% and 20% of the large-entity fee, respectively. Individual inventors and small startups usually qualify. Design patents have no maintenance fees at all, which is one quietly attractive feature of design protection.

If you want the full picture of what a patent costs from filing through its lifetime, see our breakdown of the total cost of a patent and the 2026 cost guide.

When the Clock Can Shift: PTA and PTE

The 20-year term isn't always carved in stone. Two mechanisms can push the expiration date later.

Patent Term Adjustment (PTA) compensates you for delays caused by the USPTO itself. If the patent office takes too long at certain stages of examination, you can earn day-for-day extra time tacked onto the end of your term. PTA is the system's way of saying: if we dragged our feet, you shouldn't lose protection for it.

Patent Term Extension (PTE) addresses a different problem. Some inventions—most notably pharmaceuticals—can't be sold until a regulatory body like the FDA approves them. That approval process can eat years of a patent's life while the product sits unsellable. PTE restores some of that lost time, recognizing that a drug patent is worth little if half its term burns up waiting for clearance.

Both adjustments are real but bounded. They don't hand out unlimited extra years—they're calibrated to offset specific, documented delays. Most ordinary patents see little or no adjustment, but in slow-moving fields the difference can be substantial.

What Happens When a Patent Expires

When a patent reaches the end of its term—or lapses early for unpaid maintenance fees—the invention enters the public domain. From that moment, anyone can make, use, or sell it freely, with no permission and no royalties owed to the former owner.

This isn't a loophole; it's the entire point of the patent bargain. In exchange for a time-limited monopoly, the inventor publishes exactly how the invention works. When the clock runs out, society gets to use that knowledge freely. Generic drugs hitting the market the moment a brand-name patent expires are the most visible example of this trade-off in action.

So the expiration date matters enormously—to the patent owner planning their competitive runway, and to competitors waiting for the door to open.

Quick Recap

• Utility patents: 20 years from the earliest non-provisional filing date.
• Design patents: 15 years from grant, with no maintenance fees.
• Maintenance fees (utility only) are due at 3.5, 7.5, and 11.5 years after grant—miss one and the patent expires early.
• PTA and PTE can extend the term to make up for USPTO or regulatory delays.
• At expiration, the invention is free for everyone in the public domain.

If you're just getting oriented, our explainer on what a patent actually is covers the fundamentals before you dig into terms and fees.