FDA 510(k) clearance is the most common pathway medical devices take to reach the U.S. market. It’s a premarket submission that proves a new device is “substantially equivalent” to one already legally sold, meaning it’s as safe and effective as something doctors and patients already use. The process applies to most moderate-risk devices, from blood pressure monitors to surgical instruments, and results in clearance (not approval) to sell the device commercially.
How 510(k) Clearance Works
The name comes from Section 510(k) of the Federal Food, Drug, and Cosmetic Act. A manufacturer submits a notification to the FDA before marketing a device, and the agency reviews it to determine whether the new device is substantially equivalent to a “predicate device,” which is a legally marketed device already on the market. If the FDA agrees, the device is cleared for sale.
This is different from FDA approval. The premarket approval (PMA) process, reserved for the highest-risk devices like pacemakers and artificial hearts, requires clinical trials proving a device is safe and effective on its own merits. The 510(k) pathway has a lower bar: show that your device is comparable to something that already exists. That distinction matters. A 510(k)-cleared device hasn’t necessarily been tested in clinical trials, though the FDA can request clinical data when it sees fit.
Which Devices Need a 510(k)
The FDA sorts medical devices into three risk-based classes. Class I covers low-risk items like tongue depressors and bandages. Class II covers moderate-risk devices like powered wheelchairs, pregnancy tests, and infusion pumps. Class III covers high-risk devices that sustain or support life.
Most 510(k) submissions involve Class II devices. About 74% of Class I devices are exempt from the 510(k) process entirely because they pose such low risk. The remaining Class I devices that aren’t exempt, plus the bulk of Class II devices, need 510(k) clearance before they can be sold. Some Class III devices that were on the market before 1976 (when modern device regulation began) also use the 510(k) pathway, as long as the FDA hasn’t required them to go through full premarket approval.
The Predicate Device Requirement
The centerpiece of any 510(k) submission is the predicate device. This is the existing, legally marketed device the manufacturer uses as a comparison point. Substantial equivalence is evaluated across several characteristics: intended use, design, materials, energy delivered, performance, safety, biocompatibility, and labeling.
Any legally marketed U.S. device can serve as a predicate. That includes devices previously cleared through 510(k), devices sold before the 1976 regulations took effect, and even devices that were originally Class III but later reclassified to a lower class. Manufacturers must identify one primary predicate that’s most similar to their device in terms of intended use and technology. They can reference additional predicate devices to support their case, but the FDA doesn’t allow “split predicates,” where a manufacturer cherry-picks different features from different devices to cobble together equivalence.
This system creates long chains of equivalence. A device cleared in 2025 might trace its predicate back through dozens of previous clearances spanning decades. Critics have pointed out that a modern device can end up quite different from the original device at the start of that chain, even though each individual step showed equivalence to the one before it.
What a Submission Includes
A 510(k) filing is a technical package. Manufacturers provide a device description, a comparison to the predicate device, performance testing data, biocompatibility information (showing the materials are safe for contact with the body), labeling, and software validation if the device uses software. The FDA also expects manufacturers to follow design control requirements from quality system regulations, documenting how the device was designed and verified throughout development.
There are three types of 510(k) submissions. A Traditional 510(k) is the standard pathway. An Abbreviated 510(k) leans on recognized standards or FDA guidance documents to streamline the comparison. A Special 510(k) is available when a manufacturer modifies its own previously cleared device and can use summary reporting to speed the review.
Review Timeline and Fees
The FDA’s performance goals for 510(k) review are negotiated in five-year cycles through the Medical Device User Fee Amendments. The current cycle, MDUFA V, covers fiscal years 2023 through 2027. The statutory review period is 90 days, though in practice the clock can pause when the FDA requests additional information, stretching the total elapsed time to several months or longer.
For fiscal year 2025, the standard user fee for a 510(k) submission is $24,335. Small businesses pay a reduced fee of $6,084. These fees fund the FDA’s review operations and are separate from whatever the manufacturer spends on testing and preparing the submission itself, which can run into the hundreds of thousands of dollars depending on the device’s complexity.
Possible Outcomes
The FDA’s decision comes down to one core question: is the device substantially equivalent to its predicate? If yes, the device receives a Substantially Equivalent (SE) determination, and the manufacturer can legally market it. If no, the device gets a Not Substantially Equivalent (NSE) determination. An NSE decision means the device cannot be sold through the 510(k) pathway. At that point, the manufacturer can reclassify the device, file a de novo request for novel low-to-moderate-risk devices, pursue the full PMA process, or modify the device and resubmit.
The FDA can also place a submission on hold if it’s missing critical information, or the manufacturer can withdraw it voluntarily to address deficiencies and refile later.
When a New 510(k) Is Required
Clearance isn’t permanent in every sense. If a manufacturer significantly changes a cleared device, a new 510(k) submission is required. The trigger is any modification that could significantly affect safety or effectiveness, or any major change in intended use. Specific examples include:
- Changes in who uses it or where: switching from prescription to over-the-counter, adding a new patient population, or moving from hospital use to home use
- Design and material changes: altering device design, changing material composition, or modifying sterilization methods
- Functional changes: adding wireless communication, changing the user interface, or modifying how frequently or how long the device is used
- Software changes: any update that introduces a new risk, modifies an existing risk that could cause significant harm, or significantly affects clinical functionality
Manufacturers are responsible for documenting their reasoning when they decide a change does or doesn’t require a new submission. If they get it wrong and market a modified device without proper clearance, the device is considered adulterated under federal law.
Clearance vs. Approval vs. Registration
These terms get confused constantly, even by manufacturers. “Cleared” is the correct word for a device that passes 510(k) review. “Approved” applies only to devices that go through the PMA process. “Registered” simply means a manufacturer has listed its facility and devices with the FDA, which is a separate administrative requirement that applies to all device makers regardless of their clearance pathway. When you see a product marketed as “FDA approved” but it went through 510(k), that’s technically incorrect, and the FDA has issued warning letters to companies for making that claim.