Aviation · 14 CFR 91.155 · Class B
VFR weather minimums in Class B airspace.
Three statute miles of flight visibility and clear of clouds. Enter your conditions to check them against the table.
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VFR minimums check
The Class B minimums
In the table in 14 CFR 91.155(a), Class B is the one row with no cloud-distance numbers: 3 statute miles of flight visibility and clear of clouds. The AIM repeats this in its Class B definition: "The cloud clearance requirement for VFR operations is 'clear of clouds.'"
Weather is not the only gate
The AIM (3-2-3) states that "Regardless of weather conditions, an ATC clearance is required prior to operating within Class B airspace." Meeting the 91.155 minimums does not give you that clearance. Under 91.155(d), no one may take off, land or enter the traffic pattern, under VFR, within the lateral boundaries of the surface area of a Class B, C, D or E airspace designated for an airport unless ground visibility at that airport is at least 3 statute miles (or, if ground visibility is not reported, flight visibility is at least 3 statute miles). Paragraph (c) adds that no one may operate beneath the ceiling under VFR within controlled airspace designated to the surface for an airport when the ceiling is less than 1,000 feet. Paragraphs (c) and (d) are both subject to the special VFR provisions of 91.157, which this page does not cover.
Worked example
A pilot with an ATC clearance is inside Class B at 4,000 feet MSL with 5 statute miles of flight visibility and a cloud layer in the distance. The visibility is above 3 statute miles and the pilot is clear of clouds, so the 91.155(a) Class B row is met. If the reported ground visibility at the primary airport is 2 statute miles, 91.155(d) still bars a VFR takeoff or landing there unless a special VFR clearance applies.
What the row does not say
"Clear of clouds" means no cloud-distance numbers apply. It does not allow flight in clouds under VFR. Class B certificate and equipment rules are on the Class B requirements page.
The full 91.155(a) table
| Airspace | Flight visibility | Distance from clouds |
|---|---|---|
| Class A | Not applicable | Not applicable |
| Class B | 3 statute miles | Clear of clouds |
| Class C | 3 statute miles | 500 ft below, 1,000 ft above, 2,000 ft horizontal |
| Class D | 3 statute miles | 500 ft below, 1,000 ft above, 2,000 ft horizontal |
| Class E, below 10,000 ft MSL | 3 statute miles | 500 ft below, 1,000 ft above, 2,000 ft horizontal |
| Class E, at or above 10,000 ft MSL | 5 statute miles | 1,000 ft below, 1,000 ft above, 1 statute mile horizontal |
| Class G, 1,200 ft or less above surface, day | 1 statute mile | Clear of clouds |
| Class G, 1,200 ft or less above surface, night | 3 statute miles | 500 ft below, 1,000 ft above, 2,000 ft horizontal |
| Class G, over 1,200 ft above surface, below 10,000 ft MSL, day | 1 statute mile | 500 ft below, 1,000 ft above, 2,000 ft horizontal |
| Class G, over 1,200 ft above surface, below 10,000 ft MSL, night | 3 statute miles | 500 ft below, 1,000 ft above, 2,000 ft horizontal |
| Class G, over 1,200 ft above surface, at or above 10,000 ft MSL | 5 statute miles | 1,000 ft below, 1,000 ft above, 1 statute mile horizontal |
Helicopter values for Class G (1/2 statute mile day, 1 statute mile night, clear of clouds, at 1,200 feet or less above the surface) are in the same table in the regulation.
FAQ
What are the VFR weather minimums in Class B airspace?
3 statute miles of flight visibility and clear of clouds, under the 14 CFR 91.155(a) table.
Is there a cloud distance requirement in Class B?
No numeric distances. The table says clear of clouds, which means staying out of clouds.
Do the weather minimums replace the ATC clearance?
No. The AIM says an ATC clearance is required before operating in Class B regardless of weather.
What is the ground visibility rule at the airport?
Under 91.155(d), VFR takeoffs and landings in the surface area need at least 3 statute miles of ground visibility, with the 91.157 special VFR exception.
Does this page cover special VFR?
No. Special VFR is covered separately in 14 CFR 91.157.
Sources
Retrieved 2026-11-02. Regulation text read through the eCFR API (current as of 2026-10-29); AIM text read from the FAA publication URL below. Rules change; check the current text.
- 14 CFR 91.155, Basic VFR weather minimums: the table, paragraphs (b) to (e).
- AIM chapter 3, section 2, Controlled airspace: Class B definition and the clearance requirement.
Not legal advice or flight instruction
This page summarizes federal aviation rules for general information. It is not legal advice or flight instruction and does not replace the regulation, an instructor, or the FAA. Check the current rule and your own certificate privileges before you fly. Everything runs in your browser; nothing you enter is sent anywhere.