FCC file and FCC ID

Author Hugues Orgitello Last updated 11 July 2026 ~5 min read

FCC · Pillar

The FCC file submitted to the TCB comprises 8 to 12 standardised documents. Unlike the European file kept by the manufacturer, the FCC file is published in the EAS (Equipment Authorization System) with partial public access, internal schemas typically remaining confidential but photos and manuals accessible.

The FCC ID

Structure

The FCC ID consists of two parts:

<Grantee Code><Product Code>

Grantee Code: 3 or 5 alphanumeric characters, assigned once for life by the FCC to the certificate holder (fee: $35).
Product Code: 1 to 14 characters chosen by the holder (letters, digits, hyphens).

Examples:

2AB4Z-SP-CT-100
RYK-SPCT-100
A3LSM-J100

Grantee Codes starting with a letter have 3 characters (legacy assignments, like RYK or A3L above); codes starting with a digit from 2 to 9 have 5 characters (current assignments, like 2AB4Z).

EAS search

Any FCC ID can be searched publicly in the Equipment Authorization System:

https://apps.fcc.gov/oetcf/eas/reports/GenericSearch.cfm

The search reveals:

The grantee (manufacturer or certificate holder)
Assignment date
Authorised frequencies and powers
Public documents: photos, manuals, some test reports

Confidential documents (internal schemas, detailed functional description) are protected by a Letter of Confidentiality submitted during certification.

Letter of Confidentiality

Manufacturers can request permanent confidentiality for certain documents (typically schemas, detailed functional descriptions). The request is made via a Letter of Confidentiality signed by the grantee, submitted to the TCB with the file.

Documents that may be protected:

Internal schemas
Detailed block diagram
Proprietary modulation descriptions
Technical trade secrets

Always public documents:

External photos
User manual
Label sample
Cover letter (non-confidential summary)

A short-term confidentiality (180 days typically) may also be requested for products with future launch, but it expires automatically.

File submitted contents

Administrative documents

Form 731 (Application for Equipment Authorization): TCB's electronic form
Cover letter describing the product, radio modes, tested configurations
Grantee authorization letter if submitter differs from grantee (e.g. consultant)
Letter of Confidentiality (optional)

Technical documents

Test report signed by an accredited lab, covering all applicable Parts
Block diagram electrical and functional
Schematics detailed
Operational description, explanation of radio modes, modulations, protocols
Antenna specifications, gain, pattern, impedance

Visual documents

External photos, external views of the product from all angles
Internal photos, disassembled product with FCC ID label visible and RF components identifiable
Label sample, image of the label with FCC ID and warnings

User documents

User manual complete, with Part 15.19 / 15.105 / 15.21 mentions as applicable
Quick start guide if separately provided
Safety guide if applicable

SAR / MPE documents

SAR report for worn equipment
MPE evaluation for fixed equipment (often simple documentary calculation)

Physical affixing of FCC ID

The FCC ID must appear legibly and indelibly:

General rules

Minimum height: no absolute minimum, but must be legible at normal use distance.
Indelibility: not removable by normal use or light cleaning.
Colour: contrasting with background.
Position: visible without disassembling the product.

Minimum label format

FCC ID: 2AB4Z-SP-CT-100

Or for products containing a certified module:

Contains FCC ID: <module FCC ID>

e-label (since 2014)

For products with screen, e-label is admitted per KDB 784748:

FCC ID displays via menu accessible in 3 steps maximum from main menu
Access must not require password, login or special access codes
A physical label remains mandatory on packaging

Very small products

For products too small to carry the FCC ID:

FCC ID appears on packaging and manual
A removable label may be attached for initial sale

File retention

The file is:

Published in EAS (public part) by the TCB
Retained by the holder (Grantee): 47 CFR 2.938 requires at least one year after marketing is permanently discontinued for certification records (two years for SDoC records), or until the end of any ongoing FCC investigation
Available to FCC on request for inspection

Keeping the records for the whole commercial life of the product is good practice. Retention includes all test reports, even those not submitted (intermediate tests, retests). In case of Permissive Change (modification), complete history must be maintained.

Permissive Changes, modifications after certification

Three classes of modifications after FCC ID assignment:

Class I Permissive Change (C1PC)

Modifications that do not degrade the characteristics reported at certification (47 CFR 2.1043):

Cosmetic changes (colour, design)
Equivalent non-RF component changes
Software modifications without radio impact

No TCB filing required. To be documented in internal file.

Class II Permissive Change (C2PC)

Modifications that degrade the reported performance while remaining compliant:

Antenna change (with equivalent or lesser gain)
Minor radio software modification
Equivalent RF component change

TCB filing required but simplified (no new FCC ID, grant update), and the modified product must not be marketed before acceptance. Typical cost: $2,000 to $6,000.

Class III Permissive Change (C3PC)

Reserved for Software Defined Radios (SDR): software changes that alter frequency range, modulation type or maximum power outside the approved parameters, without hardware change.

Substantial hardware modifications (band change, new modulation, power increase, radio architecture change) are not permissive changes: they require a new complete certification with its tests and a new FCC ID.

Post-market audit and compliance

The FCC may conduct audits on marketed products:

Verification of FCC ID affixing
Verification of consistency with submitted file
Compliance tests on samples (Market Surveillance)

Non-compliance sanctions include:

Cease and desist marketing-stop order
Recall product recall
Forfeitures fines (2025 inflation-adjusted amounts: up to $25,132 per day of continuing violation, capped at $188,491 per act, revised annually)
Revocation FCC ID withdrawal

A voluntary recall procedure is generally preferable to the formal FCC procedure.

Special cases

Co-located transmitters

When multiple transmitters coexist in the same product (Wi-Fi + BLE + cellular), co-existence tests may be required:

Maximum simultaneous emission complying with individual limits
No excessive mutual degradation
Documentation of minimum distance between antennas

Software-defined radios

For SDRs with software-modifiable radio configurations, documentation includes:

List of authorised configurations (bands, powers, modulations)
Protection mechanisms against unauthorised configurations
Signed software update procedure

These points are minor in the US compared to the EU (RED 3.3), but the FCC is starting to publish KDBs on the topic (notably for 6 GHz AFC).