Understanding the FDA 510(k) Submission Timeline
The FDA 510(k) submission timeline is often described as a "90-day review." The reality is more nuanced. For many medical device manufacturers, 510(k) clearance is a critical milestone on the path to commercialization. Knowing the key milestones in the review calendar helps you set realistic expectations, allocate resources effectively, and avoid unnecessary delays.
Day 1: Submission Received
The timeline begins when the FDA receives a complete 510(k) submission. Before review can start, the agency verifies that the required user fee has been paid. It also checks that the package meets electronic submission requirements, including use of the eSTAR format.
Within about seven days, the FDA typically issues one of two things. The first is an acknowledgment letter that assigns a 510(k) number. The second is a hold letter that identifies administrative issues to resolve before review can proceed.
Day 15: Acceptance Review
The first formal milestone is the Acceptance Review, commonly known as the Refuse to Accept (RTA) review. The FDA determines whether the submission is administratively complete and contains the information needed for substantive review.
If the FDA finds deficiencies, it may place the submission on RTA Hold. You then have up to 180 calendar days to address them. If you do not respond within that time, the submission is considered withdrawn.
Passing the Acceptance Review moves the submission into substantive review.
Day 60: Substantive Review
By about Day 60, the FDA completes a detailed scientific and regulatory review and provides what is known as a Substantive Interaction. This is one of the most important communications in the process. At this stage, the FDA generally takes one of two approaches:
Continue the review through Interactive Review, using emails or phone calls to resolve minor questions.
Issue an Additional Information Needed Notification (AINN) if significant deficiencies remain.
Interactive Review does not stop the FDA review clock. It is often viewed as a positive sign that the remaining questions can be resolved efficiently.
| Interactive Review (clock keeps running) | AINN Hold (clock stops) | |
|---|---|---|
| When the FDA uses it | Only minor questions remain after the Substantive Interaction | Significant deficiencies remain |
| How it works | Emails or phone calls to resolve questions | The submission is placed on hold while you prepare a complete response |
| Effect on the review clock | Does not stop the FDA review clock | Stops the FDA review clock |
| Your response window | Handled during the review, with the clock still running | 180 calendar days, with no extensions |
| What it signals | Often viewed as a positive sign that questions can be resolved efficiently | No complete response within 180 days means the submission is withdrawn and must be resubmitted |
Additional Information Needed Notification Hold
An AINN places the submission on hold while you prepare a response. The submitter has 180 calendar days to provide a complete response, and the FDA grants no extensions. If a complete response does not arrive within 180 days, the submission is considered withdrawn and must be resubmitted.
Because the FDA review clock stops during this period, the actual calendar time to clearance can be much longer than 90 days.
Day 90: FDA Decision Goal
Under the Medical Device User Fee Amendments (MDUFA) performance goals, the FDA's target is a decision within 90 FDA Days. FDA Days do not include periods when the submission is on hold waiting for the manufacturer's response to an AINN. The FDA publishes these milestones on its 510(k) submission process page. The final decision may be:
Substantially Equivalent (SE), which results in 510(k) clearance.
Not Substantially Equivalent (NSE), which requires a different regulatory pathway or additional development work.
Day 100: Missed MDUFA Communication
If the FDA does not reach a decision within 100 FDA Days, the agency is expected to issue a Missed MDUFA Communication. It explains the remaining issues and gives an estimated timeline for completion.
The Real-World Timeline
Although the FDA's review goal is 90 FDA Days, many submissions take longer in calendar time. Common causes include Additional Information requests, testing gaps, labeling questions, software documentation deficiencies, and substantial equivalence concerns. For many manufacturers, total elapsed time from submission to clearance runs from five to seven months, and longer for more complex devices.
The best way to stay on schedule is to submit a complete, well-organized 510(k) that anticipates FDA expectations. Strong predicate selection, comprehensive testing, and a carefully prepared eSTAR submission can reduce review delays and improve the odds of a timely clearance.
At Borderless MedDev, we build the regulatory strategy and eSTAR submission your device needs, and we manage communications with the FDA along the way. Our FDA Submission Preparation and Filing team can help you file a 510(k) that holds up in review. If you have already received an RTA Hold or an AINN, our FDA Clearance Remediation team can help you plan a complete response and get back on track.