What You Can Change in FCC-Certified Devices
Products change after certification. Parts become obsolete. Antennas move. Firmware evolves. Before releasing a revised design, check whether the original FCC authorization still covers it.
This guide explains FCC permissive changes and the information needed for a useful review. Start with the actual FCC ID and grant conditions. Then compare the approved design with your proposed revision.
For an overview of the approval process, see our FCC and ISED certification guide.
Four routes to review
The engineering impact determines the route. A change description alone is not enough.
Class I
For changes that do not worsen the characteristics accepted at certification. Keep evidence supporting the decision.
Class II
For changes that worsen reported performance but still satisfy the rules. Obtain acceptance before marketing the modified version under the existing grant.
Class III
For qualifying software changes to an approved SDR. This route has specific eligibility and approval conditions.
New certification
Changes outside the permissive-change provisions require a new application. The rule specifically addresses core radio circuitry and maximum power or field-strength ratings.
Class I and II changes generally belong to the grant holder. A host manufacturer using another company’s module should coordinate with that company. A test laboratory supplies evidence; it does not replace the grant holder or certification body.
Changes worth reviewing early
Use these prompts to describe your revision. They are review questions, not automatic classifications.
Antenna and enclosure
Has the antenna type, gain, cable or position changed? Check nearby metal, plastics and mounting points. A visually small change may alter the RF environment.
PCB and components
Identify changes to the radio, clocks, filters, shielding and ground connections. Include replacement part numbers and layout drawings. Similar datasheets do not prove identical behaviour.
Firmware and operating modes
Separate interface updates from changes affecting radio emissions. Flag new channels, bandwidths, modulation settings, power controls and regional settings.
Module and host integration
Review the module instructions and grant restrictions. Check approved antennas, installation conditions, RF exposure and simultaneous transmitters. The finished host also needs a compliance review.
Our wireless device testing and Wi-Fi and Bluetooth testing pages explain how to prepare representative samples and operating modes.
Firmware changes need their own review
A firmware update is not automatically Class III. Confirm whether the radio was approved as an SDR. For other radios, assess the update against the authorization and applicable FCC software-control guidance.
Describe what the update can change. Include any effect on transmit power, channels, modulation or emissions. User interface changes and radio configuration changes should not be treated as the same task.
Prepare a clear change package
A concise comparison helps the laboratory and certification body focus on the measurements that matter.
Original approval
FCC ID, grant, conditions, reports and approved configuration.
Before-and-after drawings
Schematics, PCB revisions, antenna drawings and enclosure changes.
Parts and software
Updated bill of materials, firmware versions and change notes.
Representative samples
Approved and revised units, accessories, cables and power supplies.
Repeatable operating modes
Instructions to run each relevant radio mode and hold it during testing.
Release records
Affected models, serial-number ranges, production dates, labels and manuals.
A practical review workflow
Define the change
Record exactly what changed and why. Compare it with the approved configuration.
Plan the measurements
Identify likely effects on emissions, radio behaviour and RF exposure.
Review the evidence
Compare results and supporting documents. Confirm the proposed route with the grant holder and certification body.
Control the release
Keep the reviewed configuration traceable. Complete any required authorization steps before release.
Pre-compliance testing can help investigate design changes early. For measurement planning, see our FCC Part 15 testing services. Our submission and registration page covers the supporting documentation.
Review other markets separately
An FCC decision covers the U.S. authorization route. It does not settle every destination market. Keep a separate record of the approvals, standards and product configurations used elsewhere.
For products sold in Canada, review the ISED requirements separately. For European market planning, review the applicable legislation and Declaration of Conformity documentation.
How Stancer Testing-Lab helps
We help teams investigate antenna changes, component substitutions, PCB revisions and firmware updates. Our engineers can review the test needs, measure affected characteristics and prepare supporting reports.
Send us the original approval and a short change summary. We can then discuss the scope of testing and the information needed for the certification review.
Request a review of your revised product
Frequently asked questions
Does every revision need a new FCC ID?
No. Review the grant, technical impact and eligible change route before deciding.
Is every antenna change Class II?
No. Antenna specifications and installation conditions need a product-specific review.
Can a cosmetic enclosure change affect testing?
Yes. Material, coatings and placement can affect shielding or antenna behaviour. Record what changed and compare the configurations.
Is every firmware update Class III?
No. Class III is specific to qualifying changes in an approved software-defined radio.
Can I rely only on a replacement component datasheet?
A datasheet helps, but the installed behaviour matters. Keep the part comparison and investigate effects in the revised product.
What should a module integrator do first?
Read the module integration instructions. Contact the module grant holder before making changes that may fall outside the approved conditions.
What information should I send the laboratory?
Send the FCC ID, original reports, change summary, drawings, firmware details and sample configuration. Include the markets where you plan to sell it.
Official references
- 47 CFR 2.1043: changes in certified equipment
- FCC KDB 178919: permissive change policy
- FCC KDB 996369: transmitter module guidance
Check the current rules, guidance and grant conditions when planning a change. Equipment covered by authorization restrictions needs a separate eligibility review.
