Refusing to take guide dogs will lead to a fine, Bedford Borough Council said.
Taxi firms have been warned they face fines if they refuse to allow guide dogs into their cabs, a council said.
Bedford Borough Council said it prosecuted private hire firm Crown Cars (Bedford) Limited after it refused to take a blind man with a guide dog.
The firm pleaded guilty to the offence at Bedford Magistrates' Court under the Disability Discrimination Act 1995 and received a £250 fine and £250 costs.
Licensing officers will seek to fine firms who refuse to take guide dogs.
Keith Simmons, from the council, said: "Licensing officers were very concerned that any of its licensed drivers could refuse to accept a hiring from a visually-impaired person simply because they were accompanied by a guide dog.
"This is unacceptable and I hope that this prosecution will send out this message to all licensed drivers."
Crown Cars (Bedford) Limited was also ordered to pay a £15 victim surcharge.