Hillgate Travel is asking its 12,000 clients to back the new campaign against Air Passenger Duty (APD).
Pressure group A Fair Tax on Flying launched the latest phase of its campaign a month ago, encouraging local businesses to sign an online petition against the tax.
The online petition says: "I believe that APD is too high and call upon the Government to undertake urgent action to reduce the world’s highest air passenger tax.
It adds the tax is a "significant additional burden" and is "not fair".
Hillgate, the UK’s largest independent travel management company, is highlighting the campaign in the latest issue of its customer newsletter, the Itinerary, which is distributed to over 12,000 clients.
Managing director Anthony Rissbrook, said: "It’s crucial that policy-makers look hard at the detrimental impact of APD on the UK economy.
"APD is a hugely damaging tax, making the UK less competitive than our European neighbours and hurting our connectivity with developed and emerging markets.
"Businesses are the driving force of our economy and are vital to the economic recovery, so it is important that we make our views known about the impact of this tax on jobs, growth and connectivity with the rest of the world."
