FDA · guide

510(k) vs De Novo vs PMA: Choosing a Pathway and Typical FDA Review Timelines

Updated September 1, 2026

Start with the device class

The pathway follows the classification. Section 513(a)(1) of the Federal Food, Drug, and Cosmetic Act defines Class I as a device for which general controls 'are sufficient to provide reasonable assurance of the safety and effectiveness of the device', Class II as a device for which general controls alone are insufficient but 'there is sufficient information to establish special controls', and Class III as a device that cannot be placed in Class I or II, typically because insufficient information exists to show general or special controls provide that assurance (21 U.S.C. 360c). Class III devices generally need premarket approval; most Class II and some Class I devices go through premarket notification; a novel low-to-moderate-risk device with no predicate uses De Novo.

Substantial equivalence

A 510(k) succeeds by showing substantial equivalence to a legally marketed predicate. The statute requires the same intended use and either the same technological characteristics, or different characteristics with data showing the device 'is as safe and effective as a legally marketed device, and does not raise different questions of safety and effectiveness' (21 U.S.C. 360c(i)). Section 510(k) itself requires manufacturers to notify FDA at least 90 days before introducing the device (FDA 510(k) Clearances).

The three pathways side by side

Sources for the clocks: 21 U.S.C. 360(n) for 510(k), 21 U.S.C. 360c(f)(2) for De Novo, and 21 U.S.C. 360e(d) for PMA. The performance goals come from the MDUFA V commitment letter (MDUFA Performance Goals and Procedures, FY2023-2027).

Statutory clock versus FDA Days

The statutory numbers are calendar days on paper; the MDUFA goals count FDA Days, which exclude time the submission sits with the applicant answering deficiencies. Total calendar time is therefore longer than either number suggests. The MDUFA V letter adds a useful backstop for 510(k)s: if no decision is reached within 100 FDA Days, FDA will provide written feedback listing every outstanding issue and offer a meeting or teleconference. FDA publishes quarterly MDUFA performance reports so you can compare goals with actual results. At time of writing (September 2026), MDUFA V runs through fiscal year 2027, and FDA has posted a performance goals document for fiscal years 2028 onward (MDUFA goals FY2028); check that document for any changes to the goals above.

Why De Novo matters

A De Novo request asks FDA to classify a novel device into Class I or II instead of the default Class III. The statutory clock is 120 days, but the negotiated MDUFA goal is 150 FDA Days, and the goal percentage is lower than for 510(k)s, so plan for the longest calendar time of the three except PMA. A granted De Novo creates a new classification regulation and product code, which later devices can cite as a predicate in a 510(k).

User fees for FY2026

Fees change every October 1. The FY2026 rates, effective October 1, 2025 through September 30, 2026, are set out in the Federal Register notice (Medical Device User Fee Rates for Fiscal Year 2026):

Small business status requires gross receipts or sales of no more than $100 million for the most recent tax year and must be requested in advance. FY2027 rates will be published in a new notice; at time of writing (September 2026) confirm the current year on FDA's MDUFA fees page before budgeting.

Use the Pre-Submission program before committing

The Q-Submission program lets a sponsor request written feedback or a meeting on a planned IDE, 510(k), De Novo or PMA before filing (Q-Submission guidance). Under MDUFA V, FDA's goal is to 'provide written feedback that addresses the issues raised in the Pre-Submission request within 70 calendar days', for 90% of Pre-Submissions in the MDUFA cohort in FY2025 through FY2027 (MDUFA V commitment letter). A Pre-Sub is the right place to confirm the predicate, the product code, testing expectations and whether a De Novo is needed.

Third Party Review as an accelerator

Roughly half of 510(k)s are eligible for review by an accredited Third Party Review Organization. The statute excludes Class III devices and, unless FDA determines otherwise, permanently implantable, life-sustaining and life-supporting devices (21 U.S.C. 360m). Once the reviewer forwards its recommendation, FDA's review timeframe for a decision is within 30 days, and there is no separate user fee paid to FDA (510(k) Third Party Review Program).

A short decision sequence

1. Find the product code and regulation in the Product Classification database.
2. If a predicate with the same intended use exists, plan a 510(k).
3. If the device is novel but low-to-moderate risk, plan a De Novo.
4. If the regulation says Class III, or the risk profile demands it, plan a PMA.
5. Use a Pre-Sub to confirm the choice before spending on testing.

RegPing's FDA bot delivers new clearance, De Novo and approval notices into Discord so a team can watch competitor pathways as they land.

Where to verify

• 21 U.S.C. 360c device classes, substantial equivalence and De Novo
• 21 U.S.C. 360(n) 510(k) review timeline
• 21 U.S.C. 360e PMA timeline
• MDUFA V Performance Goals and Procedures
• Medical Device User Fee Rates for FY2026
• Q-Submission program guidance
• 510(k) Third Party Review Program

This guide is general information, not legal advice. Verify against the primary source and consult counsel before acting.