You accepted a number. A revised figure arrived. Somewhere between the two, something changed, and the explanation you received may not have been complete.
Some of that movement is genuine and unavoidable. Some of it reflects how the quote was built in the first place. Knowing which is which is worth knowing.
Legitimate movement
Fuel. Prices move and quotes are frequently built on a fuel assumption with a stated adjustment mechanism. On long sectors this is material. It should be disclosed as a mechanism at quotation, not introduced afterwards as a surprise.
Positioning. The aircraft’s position when you enquired is not necessarily its position at departure. If the aircraft’s prior booking changes, the empty flying required to reach you changes with it. This is real and it can move a number substantially.
De-icing. Genuinely unpredictable, genuinely expensive, and never included. It depends on conditions on the day and on the size of the aircraft. Anyone quoting a winter operation into a cold climate without mentioning it has not been thorough.
Slots and handling at constrained airports. Some airports have variable charges depending on time and demand. Timing changes can move these.
Overnight crew costs. If your schedule moves such that a crew must stay somewhere they were not previously staying, that appears.
Movement that should concern you
A different aircraft. If the revised quote is for a different tail number or type, you have not received a price adjustment, you have received a different product. Ask why, and ask what happened to the original.
Fees appearing that were never mentioned. Handling, catering above a basic standard, ground transfers and connectivity should all be disclosed as included or excluded at the outset. Introducing them later is not a market movement.
Movement without a stated cause. Any legitimate increase has a specific reason attached to a specific line. A revised total with no line-level explanation is not a quote, it is a number.
How to structure a quote that holds
Ask for the price broken into fixed and variable components, with the variables named explicitly. Ask what the fuel assumption is and what mechanism applies if it moves. Ask for the exclusions list in writing. Ask whether the aircraft is contracted for your specific dates or merely believed to be available.
The last of those does more work than any other. A great deal of quote movement originates in aircraft that were never actually secured.
Why the industry works this way
There is a long chain in charter between an enquiry and an aircraft, and each party in it is estimating rather than knowing. Quotes built at distance from the operator are built on assumptions, and assumptions revise.
Quotes built by someone in direct contact with the operating company move less, because fewer things in them were guessed.
That is the practical reason to care how close your provider sits to the aircraft. It shows up in the number holding.
