New 510(k) or letter to file? Device change classifier

FAQ

When does a change to a 510(k)-cleared device need a new 510(k)?

Under 21 CFR 807.81(a)(3), a new 510(k) is required when a device in commercial distribution is about to be significantly changed or modified in design, components, method of manufacture, or intended use: that is, a change that could significantly affect safety or effectiveness, or a major change or modification in intended use. FDA’s October 2017 guidances “Deciding When to Submit a 510(k) for a Change to an Existing Device” and “Deciding When to Submit a 510(k) for a Software Change to an Existing Device” set out the decision logic. When a change touches both software and hardware or labeling, FDA says to use both guidances, and if either points to a new 510(k), one is likely required.

What if the change does not need a new submission?

It still goes through QMS change control. ISO 13485:2016 clause 7.3.9 requires design and development changes to be reviewed, verified, validated as appropriate, and approved before implementation, including an evaluation of the effect on constituent parts, product in process or already delivered, and risk management inputs and outputs. Record the regulatory rationale as well (often called a letter to file). Since February 2, 2026, FDA’s Quality Management System Regulation (21 CFR Part 820) incorporates ISO 13485:2016 by reference.

How are changes to a PMA device handled?

Under 21 CFR 814.39, a PMA holder submits a PMA supplement for FDA review and approval before making a change that affects the safety or effectiveness of the device, unless FDA has advised that an alternate submission is permitted. Listed examples include new indications for use, labeling changes, a different manufacturing facility, sterilization or packaging changes, and changes to design specifications or components. Changes that do not affect safety or effectiveness may be reported in the periodic (annual) report.

Does the EU MDR have its own change-notification rules?

Yes. For devices certified under MDR Annex IX, section 2.4 requires the manufacturer to inform the notified body of planned substantial changes to the quality management system or the covered device range, and section 4.10 requires notified body approval of changes to a device with a technical documentation assessment certificate where the change could affect safety and performance or the conditions prescribed for use. Check the specific conformity assessment route and your notified body’s change-notification procedure.

Can software or AI model updates be authorized in advance?

In the US, a predetermined change control plan (PCCP) can do this. Under 21 CFR 807.81(b)(1)(ii), a new 510(k) is not required for a change that is consistent with a PCCP cleared under section 515C of the FD&C Act. Changes outside the authorized plan go back through the normal change assessment.

Is this classifier a regulatory determination?

No. It only checks the two most common triggers, a change in intended use or indications and a possible increase in risk, and labels the change type. A real assessment follows the FDA flowcharts question by question, considers the cumulative effect of changes since the last clearance, and is documented in your quality records.