Every time you buy a firearm from a licensed dealer—whether online or in-store—you'll go through a NICS background check. This federal system is designed to prevent prohibited individuals from purchasing firearms.
Understanding how NICS works helps you know what to expect during your FFL transfer and what to do if issues arise.
What Is NICS?
NICS stands for National Instant Criminal Background Check System. It's a federal database operated by the FBI that determines whether a prospective buyer is eligible to purchase firearms under federal and state law.
When you complete ATF Form 4473 at an FFL dealer, they submit your information to NICS. The system searches multiple databases to verify you're not prohibited from possessing firearms.
NICS has been operational since 1998 and processes millions of background checks annually.
What Does NICS Search?
The NICS check searches several federal and state databases:
Federal Databases
- NICS Index — Records of people prohibited under federal law
- Interstate Identification Index (III) — Criminal history records from all 50 states
- National Crime Information Center (NCIC) — Wanted persons, protection orders, and more
Information Searched
- Criminal conviction records
- Arrest records
- Domestic violence restraining orders
- Mental health adjudications
- Involuntary commitments
- Drug-related records
- Immigration status
- Dishonorable military discharges
- Fugitive warrants
The system matches your name, date of birth, and other identifiers against these records to determine eligibility.
Who Is Prohibited from Buying Firearms?
Federal law prohibits firearm possession by people in these categories:
| Prohibition | Details |
|---|---|
| Felony conviction | Any crime punishable by more than 1 year imprisonment |
| Domestic violence misdemeanor | Convicted of misdemeanor domestic violence |
| Restraining order | Subject to domestic violence protective order |
| Fugitive from justice | Warrant for arrest |
| Unlawful drug user | Includes marijuana in states where it's illegal federally |
| Mental adjudication | Court-declared mentally incompetent or committed |
| Dishonorable discharge | Military discharge under dishonorable conditions |
| Citizenship status | Non-citizens with limited exceptions |
| Renounced citizenship | People who renounced U.S. citizenship |
If NICS finds a match to any of these categories, your transfer will be denied.
How Long Does a NICS Check Take?
Most checks complete within minutes. The "instant" in NICS is usually accurate—the majority of checks return a result while you're still at the FFL.
However, response times vary:
| Scenario | Typical Timeline |
|---|---|
| Clean record, no matches | 30 seconds - 5 minutes |
| Common name requiring verification | 5-30 minutes |
| Delay for research | Up to 3 business days |
| State check required (additional) | Same day - several days |
High-volume periods (holidays, after major news events) can slow the system. Black Friday is consistently the busiest day for NICS.
NICS Response Types
After your check is submitted, NICS returns one of three responses:
Proceed
You're approved. The FFL can complete the transfer immediately (unless state waiting periods apply).
Delay
NICS needs more time to research your background. The system has identified something that requires further investigation—this doesn't mean you'll be denied.
Common delay reasons:
- Name similar to a prohibited person
- Incomplete records requiring verification
- Previous arrest with unclear disposition
- Expunged or dismissed charges showing in database
- State records requiring manual review
What happens during a delay:
- Federal law allows the FFL to transfer after 3 business days if no response is received (the "default proceed" rule)
- Many FFLs choose to wait for a definitive answer
- Some states prohibit default proceeds and require a final response
- The FFL will contact you when resolved
Denied
Your transfer is blocked. Federal or state law prohibits you from receiving the firearm.
If denied, the FFL cannot complete the transfer under any circumstances. You have the right to appeal.
What to Do If You're Delayed
A delay isn't a denial. Most delayed checks ultimately result in "Proceed" responses.
During a delay:
- Wait for the FFL to contact you with results
- The FFL cannot tell you why you're delayed (they don't know)
- Avoid calling the FFL repeatedly—they'll reach out when they have news
- Have patience—some delays resolve within hours, others take days
If you frequently get delayed:
You may have a common name or records that consistently trigger additional review. Consider applying for a NICS Appeal Services Transaction Number (UPIN). This unique identifier links to your FBI-verified background and can help future checks process more quickly.
Apply for a UPIN through the FBI: FBI NICS Appeals & VAF
What to Do If You're Denied
A denial prevents your transfer from completing. But denials aren't always permanent or accurate.
Understand Why You Were Denied
The denial letter (which you can request) will cite the reason. Common denial reasons include:
- Felony conviction — Accurate or mistaken identity
- Domestic violence conviction — May be unclear or incorrectly categorized
- Active warrant — Sometimes for minor issues you didn't know about
- Drug use — Self-disclosure on Form 4473 or recorded charge
- Mental health adjudication — Court records on file
- Mistaken identity — Someone with your name/DOB is prohibited
How to Appeal a Denial
For federal denials (most common):
- Request your denial reason from the FBI
- Gather supporting documentation (court records, expungements, proof of identity)
- Submit an appeal through NICS Appeal Services
- Wait for review (can take weeks to months)
For state denials:
Contact your state police or state point-of-contact for their appeal process.
Common Successful Appeals
Many denials are overturned for:
- Mistaken identity — Your name/DOB matches a prohibited person, but you're not them
- Expunged records — Charges were dismissed or expunged but still appear in database
- Incorrect categorization — Conviction doesn't actually meet federal definition
- Restored rights — State restored your rights after a conviction
Don't assume a denial is correct. If you believe you're eligible, pursue the appeal.
State Background Check Systems
Some states run their own background checks in addition to (or instead of) federal NICS:
| State | System |
|---|---|
| California | California DOJ |
| Colorado | Colorado Bureau of Investigation |
| Florida | Florida Department of Law Enforcement |
| Nevada | Nevada DPS (as of 2020) |
| Pennsylvania | Pennsylvania State Police |
| Tennessee | Tennessee Bureau of Investigation |
| Virginia | Virginia State Police |
| Washington | Washington State Patrol |
In these states, your FFL contacts the state system, which may also check NICS. State checks can have different timelines than federal NICS.
NICS and Waiting Periods
NICS background checks are separate from state waiting periods.
Background check: Determines if you're eligible
Waiting period: Mandatory delay before you can take possession
You might pass NICS instantly but still need to wait 3-14 days (depending on state) before receiving your firearm.
Check your state's waiting period →
Frequently Asked Questions
How far back does a NICS check go?
NICS has no time limit. It searches your entire criminal history, regardless of when offenses occurred.
Does NICS check my social media?
No. NICS searches law enforcement and court databases only—not social media, internet history, or personal communications.
Can I check my own NICS status before buying?
No. There's no way to pre-check your NICS status. The check only runs when you attempt to purchase through an FFL.
Does a concealed carry permit bypass NICS?
In some states, yes. Certain state permits qualify as NICS alternatives because they require similar background checks. Your FFL will know if your permit qualifies.
How long are NICS records kept?
If approved, NICS must destroy your identifying information within 24 hours. The FFL keeps Form 4473 records, but NICS itself doesn't maintain records of approved transactions.
What if I have a marijuana card?
Federal law still classifies marijuana as a controlled substance. Using marijuana—even legally under state law—may disqualify you under federal law. Form 4473 specifically asks about controlled substance use.
Ready for Your Transfer?
Understanding NICS helps you know what to expect. For most buyers, the background check is quick and straightforward.
Find an FFL near you to complete your next transfer.