Hotels will bring in a record $2.93 billion this year in extra charges beyond the basic room rate for things that many travelers still expect to get free.

That total, which represents an 8.5 percent increase from 2017, comes from Bjorn Hanson, a hospitality expert who has been tracking hotel fees for years. He predicts such charges will continue to rise. “Fees and surcharges are highly profitable,” Hanson said in an annual assessment of hotel industry fees. As much as 90 percent of many charges go straight to the bottom line, he said.

In the airline industry, which began imposing new charges as the recession deepened in 2008, fees have generated a great deal of passenger anger, although charges for things such as checking luggage or changing reservations have helped carriers overcome rising costs.

The hospitality industry discovered the magic of fees around 1997 when hotels needed to compensate for higher energy costs, Hanson said.

Hotels and airlines both prefer to add fees or increase existing ones rather than raise prices so as not to scare off customers who primarily consider base fares and overnight rates.

Among the relatively new fees imposed at resort hotels in the past two years are charges for early check-in, which is most common in resort areas.

Resort fees — ranging from $20 to $40 — have also become more common in urban hotels that aren’t generally considered resorts.