What Is Grey Charter?

How it works

Grey charter describes flying paying passengers for compensation on an aircraft, or by an operator, that does not hold the certificate the flight legally requires. In the United States this usually means an aircraft flown under 14 CFR Part 91 — the rule covering private, non-commercial flying — being used to carry passengers for hire, when federal law requires the flight to be conducted under 14 CFR Part 135, the FAA's on-demand charter rule, by a holder of an FAA operating certificate issued under 14 CFR Part 119. In the UK and EU the equivalent breach is operating a commercial flight without an Air Operator Certificate (AOC): in the UK, issued by the Civil Aviation Authority under the Air Navigation Order 2016; in EU member states, issued under EASA Regulation 965/2012 (Air Operations). This describes the position as it stood on 28 September 2026.

The practice takes several forms. An owner of a private aircraft might offer flights to third parties for money, on the claim that costs are merely being shared rather than that the flight is a paid charter. A broker might arrange a flight and present it to a client as a normal charter while the aircraft or operator has no valid certificate for that operation. An operator holding a certificate for one type of flying might fly a route or carry passengers outside what its certificate actually authorises. In every case, the passenger pays to fly on an operation that is not subject to the crew licensing, maintenance oversight and insurance requirements that a proper certificate imposes.

Because the flight itself looks identical from the cabin, a passenger cannot tell from the aircraft or the crew whether the operation is properly certificated. The distinction sits in paperwork: which certificate is held, by whom, and whether the specific flight falls inside what it authorises. This is why the term matters more than most in this glossary — it is not a pricing clause but a question of whether the flight is lawful at all.

Cost impact

Grey charter carries no charge of its own; its effect on price runs the other way. A flight offered outside proper certification can be quoted markedly cheaper than a legitimate charter, because the operator avoids the costs certification imposes — in the United States, the federal excise tax on air transportation under 26 U.S.C. § 4261 administered by the Internal Revenue Service, plus the maintenance and insurance regime a Part 135 certificate requires; in the UK and EU, the equivalent obligations tied to holding an Air Operator Certificate. The saving that makes an illegal quote look attractive is built from exactly those avoided costs.

Take an illustrative case in the United States: a legitimate Part 135 charter is quoted at $9,000 for a domestic flight on a light jet, with federal excise tax of approximately 7.5% adding roughly $675. A grey charter quote for the same trip, avoiding that tax and the compliance costs of a Part 135 certificate, might come in at an illustrative $7,000 — around 22% lower. Any saving passed to the passenger is bought by giving up the crew qualification, airworthiness oversight and certificate-linked liability insurance that a properly certificated flight carries; if something goes wrong, the passenger's own legal and insurance position is correspondingly weaker.

The check available to a buyer is the certificate itself: before booking, a buyer can ask which operator will fly the aircraft and confirm that it holds a valid certificate for that kind of flight in the relevant jurisdiction — in the United States an FAA operating certificate under Part 119 with Part 135 operations specifications, in the UK a CAA-issued AOC, in an EU member state an AOC issued under EASA rules. Price and appearance give no indication either way; the certificate check is the only reliable one.

Example

Suppose, for illustration, a prospective client asks a broker to arrange a one-way flight for four passengers between airport A and airport B on a light jet. One quote, from an operator holding a valid FAA Part 135 certificate, comes to an illustrative $8,500, inclusive of an approximate 7.5% federal excise tax. A second quote, presented as the same flight, comes from an aircraft owner offering to fly the trip under the private Part 91 rules for an illustrative $6,200, with no excise tax added and no operating certificate mentioned.

The second figure is lower partly because the flight, as offered, would not be conducted under Part 135 oversight, and partly because the excise tax is not being collected. Confirming which certificate, if any, the operator holds for that flight is the step that distinguishes the two quotes; booking the cheaper one without that confirmation would place the passengers on a flight that is illegal under United States federal aviation law, regardless of how it is marketed.