Since New Year’s Eve is considered one of the most dangerous days to drive, ride-hailing services will be in high demand. And for high prices.

Wednesday into Thursday is expected to be the busiest period of the year for companies such as Uber and Lyft, which use smartphone apps to connect drivers to customers, as millions are expected to use the apps. As a result, Uber will be bringing back its surge pricing.

Between 12:30 a.m. and 2:30 a.m., prices will increase at least five-times the normal rate. Full-price estimates will be given before a ride is requested and the app will notify users if the surge is in effect. Uber suggests booking a ride just after the ball drops at midnight or waiting until after 2:30 a.m. to avoid surge pricing. Also, an app called SurgeProtector can help customers find locations with lower surge prices. 

Uber is said to make at least $10 million alone. And they will donate $1 of every ride on New Year’s Eve between 6 p.m. and 6 a.m. to Mothers Against Drunk Driving if customers use the promotional code MADDNYE.

Lyft will donate $1 for every person who pledges to travel safe on New Year’s Eve as well. And Lyft users will see a similar increase in prices called “Prime Time.” The feature is activated when the number of users requesting rides largely outweighs the number of drivers. The extra amounts paid will depend on each area’s demand. The Prime Time icon located in the bottom right corner of the app’s screen will indicate the rate.

New Year’s Eve is a test for just how well both companies will be able to safely transport millions. Tens of thousands of customers and drivers are associated with both Uber and Lyft. Their workforce is expanding, and new drivers are being recruited who may have never experienced driving home intoxicated strangers through congested areas in large cities.

Although Uber and Lyft drivers do not receive extra training in preparation for New Year’s Eve, spokeswomen for the companies said the drivers constantly receive reminders through the app of traffic issues and safety precautions.  Lyft spokeswoman Paige Thelen said that Lyft is always communicating with their drivers and encouraging them to “exercise caution” on the streets especially on “busy nights such as New Year’s Eve.”

Uber and Lyft are not the only apps celebrators will be using Thursday. Apps such as Flywheel, Sidecar and BeMyDD will be used nationwide.

Flywheel, a much smaller competitor, is offering its users in Seattle, San Diego, Sacramento and San Francisco rides for $10 from 8 p.m. to 3 a.m. on New Year’s Eve as long as the metered balance remains less than $50. Time Magazine reports that this is a direct jab at Uber and Lyft.

Another app, Sidecar, works similarly to Uber and Lyft but promises that the price will be known up front. This app also contains a carpooling function which allows people with nearby destinations to share rides.

In addition, BeMyDD is a service that allows users to reserve a driver to drive a car home in case the user is intoxicated. Two drivers are involved. One will drive the user to the car and the other will give the user’s driver a ride once the user has arrived home safely. Pricing varies based on your location.

Also, AAA has as program called “Tow To Go” in Florida, Tennessee and Alabama to combat drunken drivers. This allows a free tow for members, and non-members, up to 10 miles. The tow takes the driver and the vehicle home.