In a statement on Monday (15 August), the airport said after consultation with airlines its current limitation of 100,000 daily departing passengers would run until 29 October.
In response, BTA chief executive Clive Wratten said the decision did not have the "best interest of travellers at its heart".
"It compounds the misery faced by many leisure travellers and heaps pain on British businesses trying to get back to international work," he added.
He called on Heathrow to be "truthful with its industry and all travellers" and provide clarity on what its staffing levels are and how quickly it is addressing the issue.
"As staff levels increase, surely the passenger cap can rise in order to help struggling airlines and to get British people overseas safely and efficiently," he said. "Why are they taking unilateral action rather than reflecting the reality of their progress? We all deserve better."
