It’s been described as hundreds of millions of dollars , with a top Air Force official saying the retrofit is likely to be under $400 million. Some lawmakers and reports have floated a much higher figure, potentially up to about $1 billion , depending on what security, communications, and interior changes are included.

What’s behind the cost

The lower estimate comes from Air Force testimony that the aircraft’s retrofit would likely stay below $400 million. The higher estimates reflect the fact that a presidential aircraft needs heavy security upgrades, communications systems, and other mission-specific modifications, and some reports say those broader costs could push the total much higher.

Why estimates vary

A big reason the numbers differ is that people are not always talking about the same thing. Some figures cover only the basic retrofit of the donated jet, while others bundle in work the Air Force says it would have needed anyway, plus security screening and long-term presidential-airlift changes. That is why you’ll see both “under $400 million” and “possibly $1 billion” in recent coverage.

Current reporting

Recent reporting still centers on that same range. CBS and Bloomberg have both pointed to the jet being a $400 million aircraft, while the retrofit itself is being discussed as a major additional cost. Reuters also reported that Air Force Secretary Troy Meink said the retrofit would likely be under $400 million, while Democratic lawmakers argued the total could exceed $1 billion.

Bottom line

The best current public estimate is under $400 million for the retrofit itself , but the broader debate around the full modification and security package has put the possible total as high as $1 billion.

TL;DR: the retrofit is most commonly estimated at under $400 million , though some estimates go much higher depending on what’s counted.