Until person-to-person mobile payments become widely adopted or someone develops the killer app for gratuities, business travelers who tip will still need to cough up cash on the road.

A few bucks here, $5 there, tips for shuttle drivers, skycaps, bellhops, concierge services and housekeeping — it adds up. But for everything else — restaurants, taxis and delivery services — there are ways business travelers can keep better track of their tips.

Thomas King, 23, knows this all too well. As a consultant who travels frequently, Mr. King says he does not have a choice when it comes to tipping. Junior members who travel with senior colleagues are responsible for digging into their wallets. “I do my best to write them down as I go along,” said Mr. King, who does so on his smartphone. But when he is not traveling for work, “I don’t carry cash anymore,” he said. “I really have to go out of my way to have $20 in cash in my pocket.”

Given that the typical company spends 10 percent or more of its total annual budget on expenses related to business travel, according to the Aberdeen Group, a market research firm, those miscellaneous expenditures can nick corporate coffers. That is, if a business traveler actually remembers or cares to add out-of-pocket spending on travel and expense reports.