The easiest way to make the 168-mile (270 km) journey from El Calafate to Puerto Natales—gateway to the Torres del Paine National Park—is by bus. The trip takes five and a half hours, depending on how much time it takes to cross the border. You also have the slightly more expensive but still affordable option of renting a car from several companies in El Calafate. Private transfers are also available, for a much higher price.
One thing to keep in mind: you won't be allowed to take any food across the border, so plan your snack breaks accordingly and don't bring more than you can consume during the trip.
Duration: 5.5 hours
This is the easiest and cheapest way to travel directly from El Calafate to Puerto Natales. There are two companies that make this trip, Bus Sur and Cootra, with morning departures on Monday, Wednesday, Friday, and Sunday all year round. During peak season, from November through February, there are more buses including afternoon departures on some weekdays. Keep in mind there are no Tuesday or Thursday buses available during the off-season.
Buses depart from the El Calafate bus terminal located on Antoine de Saint Exsupery. It is recommended to book your tickets in advance and you must arrive at the station a half-hour prior to departure. Buses are comfortable and have air conditioning and bathrooms onboard. The views are scenic, but don't offer much variety—make sure to bring a book or have some other entertainment on hand.
By Rental Car or Private Transfer
Duration: 5-5.5 hours
Driving from El Calafate to Puerto Natales offers you the most flexibility and costs slightly more than the bus. You can rent cars from Hertz, Avis, and Budget or from a local company like Servicar. You will have to navigate crossing the border yourself, but this is generally fairly easy and takes on average 20-30 minutes. Make sure you have the necessary documentation. The drive is safe and mostly smooth—though, you will encounter some gravel roads as you get closer to Puerto Natales. It's recommended you fill up on gas in Argentina, where it's significantly cheaper than in Chile.
Private transfers are also available. If your final destination is Torres del Paine, there are private shuttles that will take you straight there without stopping in Puerto Natales. Ask a local specialist for more details.