Surge or dynamic pricing are methods Uber and Lyft uses to incentivize more drivers to take to the roads when rides are in high demand—for example, during sporting events, holidays, or inclement weather. Prices are algorithmically determined and can vary by neighborhood or time.

“Given we’re expecting millions of rides to occur on just this one night, fares will likely be higher than usual,” Uber said in a release.

So what can you expect?

While the surge amount itself is subject to change due to to real-time, location-specific demand, Uber provided time windows when fare prices are expected to peak. Riders can expect the highest fares between midnight and 3:00 a.m. local time.

According to the Los Angeles Times, riders should also be mindful of high fares between 8 p.m. and 11 p.m. local time on New Year’s Eve.

Uber explained they’ll “show you the price before you request your ride so you know how much you’ll pay.”

“And when fares are much higher,” the company continues, “you’ll be asked to confirm the higher fare before request.”

In past years, Lyft has also inflated prices during peak hours, though those prices were capped. In a statement to Fortune Lyft said they, too, will have “dynamic pricing” on New Year’s Eve.

“We are looking forward to offering affordable, reliable, and convenient transportation on New Year’s Eve and do everything we can to ensure there are enough drivers available for those using Lyft to move around on this busy night. Lyft’s dynamic pricing allows us to maximize the number of rides available for passengers by incentivizing drivers to get on the road when demand is high. When the ride requests from passengers greatly outnumber available drivers on the road, our system will automatically turn on Prime Time. When Prime Time is in effect, passengers are alerted and required to confirm they accept the multiplier before requesting a ride.”

So how do you avoid these high fares?

If you’re looking to sidestep Uber altogether, you can walk to a local destination, have a designated driver (you did drink all that bubbly we recommended, didn’t you?), take public transportation, or hail a traditional taxi cab. Hosting New Year’s Eve festivities at your own home is also a way to dodge surge prices.

For those who still plan on using a ride share app, it’s a numbers game.

Getting to your destination before surge pricing begins, and timing your exit to hit between the peak fare windows should theoretically help keep costs down.

Sharing a car is also recommended. Uber suggests using uberPOOL, its carpooling option, which is less expensive than uberX, or splitting cars with friends to keep the costs low.

Lyft suggests using their carpooling option Lyft Line, or scheduling a ride in advance.