National Express West Midlands were forced to put on a "skeleton service" – which involved 235 drivers – on vital routes after indefinite strike action from Unite members.
Around 3,100 members overall voted by 71 per cent against the proposed 14.3 per cent rise, which led to the network being almost decimated with limited services running.
The bus company, which said its door remained open for talks, said around 56,000 journeys took place on Monday, day one of the strike action, as it apologised to customers.
A spokesman said: "We want to say a huge thank you to all our drivers who got out there (on Monday) and did their bit for the travelling public.
"We are very sorry to our customers for the inconvenience of the strike and we are adding more services in every day so please check our website for what is running.
"We made an excellent offer of 14.3 per cent pay increase to our drivers, which would take the typical driver to £33,000 a year, and our door remains open for talks.
"We want to reassure our customers we are doing all we can to resolve this issue."
Unite has argued the company makes "considerable profits" from the hard work of staff who are "not paid enough for the difficult and stressful job they do".
Sharon Graham, the union's general secretary, added: "The company must come back with an offer our members can accept.
"Unite’s top priority is defending and improving our members’ jobs, pay and conditions and National Express’ workforce have their union’s full support during these strikes."