Part 91 is the FAA’s general operating rulebook for private, non-commercial flying; Part 135 is the stricter rulebook an operator must hold a certificate for before it can carry passengers for pay. The practical difference shows up in hard limits: on a Part 135 charter, a two-pilot crew can log no more than 10 hours of flight time in 24 consecutive hours and must have at least 10 consecutive hours of rest beforehand (14 CFR 135.267), while Part 91 sets no federal duty or rest limits at all.
For passengers, that means a paid charter flight must be flown under Part 135. For aircraft owners, it means choosing whether your jet stays a private Part 91 aircraft or is placed on an operator’s Part 135 certificate so it can earn charter revenue. This guide explains both sides, with the specific rules that change, the tax consequences, and the questions to ask before you fly or sign a management agreement.
Part 91: the owner flying their own aircraft. Part 91 covers civil aircraft operating without compensation for the flight: an individual or company flying its own jet for its own purposes, with its own or contracted pilots. The owner (or the owner’s flight department) holds operational control, meaning it decides whether, when and how each flight operates.
Part 135: anyone paying for a seat or a whole aircraft. When a passenger or company pays for air transportation, the flight must be conducted by a certificated air carrier under Part 135, and that certificate holder, not the passenger or the aircraft owner, holds operational control. That includes on-demand charter, one-way repositioning legs sold to the public, and charter flights flown on a managed aircraft.
Part 91 Subpart K: the fractional exception. Fractional ownership programs operate under their own set of rules within Part 91 (Subpart K), which adds duty-time and management requirements of its own. It is not the same as Part 135 and is not available for a one-off trip.
The same aircraft and the same pilots can fly under either rulebook on different days. What changes is the regulatory floor that applies to that flight:
| Area | Part 91 (private / non-commercial) | Part 135 (on-demand charter) |
|---|---|---|
| Who holds operational control | Aircraft owner or operator | The certificate holder (the charter operator) |
| Pilot flight time | No federal limit | 8 hrs per 24 hrs (one pilot); 10 hrs (two pilots) — 14 CFR 135.267 |
| Crew rest | No federal requirement | At least 10 consecutive hours before each assignment; 13 rest periods of 24+ hours per quarter |
| Duty period | No federal limit | Assigned duty period of up to 14 hours, bracketed by 10-hour rest periods |
| Pilot checks | Flight review every 24 calendar months plus currency | Recurring competency checks and, for IFR captains, instrument proficiency checks under the operator’s FAA-approved training program |
| Drug and alcohol testing | Not required | Required (14 CFR Part 120) |
| Landing runway margin (large turbine jets) | Aircraft performance limits | Must be able to stop within 60% of the effective runway length at the destination; 115% of that if the runway may be wet (14 CFR 135.385) |
| Weather | More discretion on low-visibility takeoffs and approaches | Stricter takeoff, approach and weather-reporting requirements |
| Maintenance | Manufacturer program or owner-selected inspection program | Operator’s FAA-approved maintenance program, conformed to Part 135 equipment requirements |
| Passenger ID | Not ordinarily required domestically | Government photo ID for passengers 18+ |
| Federal excise tax | Not charged; higher noncommercial fuel tax instead | 7.5% ticket tax plus $5.30 per passenger per domestic segment in 2026 |
Sources: 14 CFR 135.267 and 135.385 via Cornell Law’s Legal Information Institute; 2026 excise tax rates from the FAA’s Current Aviation Excise Tax Structure and Rates 2026.
It is the legal requirement, not an upgrade. If you are paying for a flight, it must be flown by a Part 135 certificate holder (or a Part 121 airline). A flight sold for money and flown under Part 91 is an illegal charter, and insurance coverage on such a flight can be in doubt.
The extra margins are built into your trip. The runway rule is why an operator may decline a short runway that the same aircraft uses privately, or reduce fuel or passengers on a hot day. The duty rule is why a long day with a late return can require a second crew or an overnight. These are not padding; they are the rules your quote is built around.
Ask who operates the flight. Many charter sellers are brokers, not operators. Ask which company’s Part 135 certificate the flight is on, and confirm that company is the one with operational control. A legitimate broker must disclose this.
Charter revenue is the main reason to go Part 135. Placing your aircraft on a management company’s certificate lets that operator charter it to third parties when you are not using it. Revenue from those trips offsets fixed costs such as crew salaries, hangar, insurance and training. How much it offsets depends on aircraft type, base, availability and the revenue split in your agreement.
You give up some flexibility. On charter flights you are a customer of the operator, not the person in control. Even when you fly your own aircraft, if it is operated under the operator’s control, expect Part 135 runway, weather and duty limits to apply, and the trip may be taxable as commercial transportation.
The aircraft must be conformed. Before charter, the aircraft is inspected and added to the operator’s operations specifications. This can require equipment changes and moves maintenance onto the operator’s approved program. Plan for downtime and a one-time onboarding cost [NEEDS NUMBER FROM OPS: typical Silver Air onboarding time and cost range by aircraft class].
Taxes and depreciation change. When an owner surrenders operational control, flights can be treated as commercial for IRS purposes, which affects excise tax and depreciation schedules. State sales, use and property tax treatment varies. This is a question for your aviation tax adviser before you sign, not after.
Liability shifts. The certificate holder bears primary regulatory responsibility for charter flights it operates, though owners should still review insurance limits and named-insured provisions in the management agreement.
Silver Air Private Jets has been an FAA Part 135 operator since its founding in 2008, so every charter we sell on our managed fleet is flown on our own certificate, under our operational control. The managed fleet spans the Pilatus PC-12, Citation CJ3, Citation Latitude, Citation X, Challenger 350 and 605, Gulfstream G-IV SP, GV and G550, and Global Express. Silver Air holds Wyvern Wingman PRO status and an IS-BAO registration, and each flight is run through a flight risk assessment as part of our safety management system.
For owners, our aircraft management program, including PURE Jet Management, can keep your aircraft private under Part 91 or place it on our Part 135 certificate for charter revenue. We will walk you through what each option means for your flying, crew and costs [NEEDS NUMBER FROM OPS: management fee structure and owner revenue share]. If you are a passenger comparing charter options, see our charter page or our safety and certifications.
What is the difference between Part 91 and Part 135 in simple terms?
Part 91 is the baseline rulebook for private flying where no one pays for the flight. Part 135 is the commercial rulebook for on-demand charter, with added rules on crew duty and rest, training, maintenance, runway margins, weather and drug testing.
Is Part 135 safer than Part 91?
Part 135 sets a higher regulatory minimum and requires FAA oversight of the operator’s training and maintenance programs. A well-run Part 91 flight department can operate to similar or higher internal standards, but nothing in Part 91 requires it.
Can I pay someone to fly me on a Part 91 aircraft?
Generally no. Carrying passengers for compensation requires a Part 135 (or Part 121) certificate, apart from narrow cost-sharing and time-sharing exceptions in Part 91. If someone offers you a paid flight under Part 91, treat it as a warning sign.
Can my private jet be used for charter?
Yes, if it is added to a Part 135 operator’s certificate, typically through a management agreement. The aircraft must be inspected and conformed, and the operator takes operational control of charter flights.
Which aircraft management companies can put my jet on their Part 135 certificate?
Only management companies that also hold a Part 135 certificate, such as Silver Air. Some managers handle Part 91 aircraft only, so ask directly, and ask how revenue, fees and owner usage are handled.
Does Part 135 charter cost more because of taxes?
Commercial flights carry the 7.5% federal excise tax plus a $5.30 per-passenger domestic segment fee in 2026, according to the FAA’s published rates. Private Part 91 flights instead pay a higher noncommercial jet fuel tax of 21.8 cents per gallon.
What is Part 91K?
Subpart K of Part 91 governs fractional ownership programs. It adds management and duty rules beyond basic Part 91 but is a separate framework from Part 135 charter.
Why did my charter operator say no to an airport my friend flies into privately?
Part 135 runway, weather-reporting and performance rules are stricter. A runway that works under Part 91 may not leave the margin Part 135 requires for that aircraft, weight and weather. Have questions about a specific trip? Contact our team.
Reviewed November 3, 2026 by the Silver Air team.
