Pilot tests are beginning with two of the biggest Mercedes dealership groups in the Germany, BERESA and LUEG, Mercedes said in a statement.
Subscription customers can select and drive up to 12 new vehicles for a year at a fixed monthly rental rate, which Mercedes did not disclose. The rate includes insurance, maintenance, repair, tires and up to 36,000 km (22,369 miles) a year.
Customers make vehicle changeovers online through the Mercedes me Flexperience app.
Mercedes said the subscription service is different than ownership or renting a car because customers can select the engine line-up, color and interior fittings. They can also upgrade to a higher vehicle class at any time.
Subscribers can choose vehicles from one of four segments: A-, C-, E- and S-class models and their SUV/crossover and sporty offshoots. Subscriptions will be offered for each of the four vehicle classes.
"If you want upgrade, you have to pay," Mercedes head of sales, Britta Seeger, said on the sidelines of the Geneva auto show. "For example, if you have your wedding day and you are subscribed in a C class and you want an S-class cabriolet — you can, but you have to pay."