Metro riders will be able to board a bus or train without a fare card or cash within a few days, just in time for some of the transit agency’s heaviest use during the Houston Livestock Show and Rodeo.

Metropolitan Transit Authority officials on Wednesday said they had completed testing and preparation and will activate a smartphone payment system Monday or Tuesday. The rodeo starts Tuesday, and the mobile ticketing will include the option to buy rodeo shuttle tickets.

“We want to make sure everything is in place, but it will be live by the time the rodeo opens,” Metro spokesman Jerome Gray said.

Officials plan a launch event, possibly linked to the rodeo opening, to publicize the new mobile ticketing option.

Bus and train use surges during the rodeo, as tens of thousands of visitors each day descend on NRG Park. Metro also offers parking at some of its park and ride locations and operates shuttles to NRG Park.

Work on the smartphone payment system started last year, with the aim of having riders pay and show proof of a valid ticket on their mobile phone by the end of 2015. Customers, notably frequent riders and people under age 45, have clamored for a phone-based ticketing option, officials said.

Metro’s app allows a rider to use PayPal or a credit card to purchase and store tickets. Once activated, the tickets are valid for three hours. The system includes elements to eliminate fraud.

A number of cities, notably Portland, Ore., and Dallas, beat Houston to offering mobile tickets. In both of those cities, despite some technology-related problems, many riders embraced the system. TriMet, the transit agency for Portland, sold about 2.9 million mobile tickets in 2014, about 3 percent of all trips.

Transit use in Houston is lower than in the Portland area.

Not all functions Metro plans to unveil will be active by next week, said Denise Wendler, the agency's chief information officer. The contract includes offering Apple Pay, Google Wallet and Android-based payment systems, but those are not included yet.

Wendler said it will also take longer to allow students to purchase discounted fares, though other ticket options will appear much sooner.

“The very next thing we do is park and ride,” Wendler told a Metro board committee.

Officials predicted many riders – especially younger ones – will convert to smartphone payments.

“It’s just easier for them,” board member Diann Lewter said. “I think it is great.”

The system also allows for buying and using multiple tickets, something Lewter said she thought families would embrace.

“It’s one less thing to fool with,” she said. “You don’t have to stand in line and buy tickets.”