Amid the ongoing conflict in Iran and surging fuel costs, your vacation could increase in price even after you’ve paid or be canceled outright.

Oil prices have risen more than 40% since Operation Epic Fury got underway on Feb. 28.

Fuel routes have also been disrupted, and airlines and cruise ships alike are adapting by increasing prices, shifting schedules, and adding surcharges.

“Prices have already risen this year, but we haven’t seen the end of it. Travelers will be paying more over the coming months,” Paul Charles, chief executive of luxury travel consultancy the PC Agency, told ITV1.

According to the latest International Air Transport Association data, jet fuel prices increased from $99 per barrel at the end of February to $209 at the beginning of April – although they have fallen in recent weeks to $179.

These extreme fluctuations are reflected in unprecedented changes in travel.

Spanish budget airline Volotea enraged passengers by reportedly asking them to pay extra fuel charges after their tickets had already been purchased.

The airline has a clause that allows it to tack on charges based on oil prices. Volotea refers to the rule as its “Fair Travel Promise.”

At first glance, the added charge — which will be $8 to $11 per passenger, per the “Simple Flying” aviation blog — does not sound high.

But travelers are concerned the fee could herald higher prices and surprise fees for additional airlines.

Regarding the high price of the high seas, and as Cruise Radio reports, the majority of cruise lines reserve the right to add a daily surcharge if oil hits a certain threshold, a brink we are now well beyond. This right is written into the fine print of nearly all cruise contracts.

Other airlines have also begun cutting routes, scaling back flight schedules, and raising fares.

The timing is especially challenging as the summer travel season is one of the busiest times of the year.

Air France-KLM said it had increased fares, while Air Canada has suspended some routes, citing jet fuel prices as the reason they are no longer “economically feasible.”

Lufthansa is reportedly leading with about 20,000 summer flight cancellations to conserve fuel, while Norse Atlantic has fully withdrawn from Los Angeles, dropping all summer Europe routes.

Domestically, Delta is trimming at least eight regional routes 

Charles warned that this trend could accelerate and that travelers should be on high alert.

“You need to be checking your emails and your messages every day, because the airlines themselves are under pressure to cancel flights, maybe for profitability reasons or because there’s not enough jet fuel,” he said

“It’ll be choppy over the next few weeks. There will be delays, there will be cancellations, and it’s not for the faint-hearted,” he added.

Brits who pre-book vacations are particularly vulnerable to price hikes.

Under the UK’s Package Travel Regulations law, agencies can add up to 8 percent to the cost of a package vacation without offering the right to cancel. Any increase of more than 8 percent is subject to cancellation for a full refund.

This right to raise prices can be exercised if there’s a significant change in fuel costs or the currency, and/or if the destination levies additional taxes.