The British Airways check-in worker banned from wearing a cross to work faced a final appeal against the decision earlier in the week.
Although Nadia Eweida, 55, lost her first appeal last month, she had one last chance to fight her case.
Ms Eweida has been on unpaid leave since October when bosses told her to remove the cross because it went against the company's uniform policy.
Critics condemned the policy as a double standard that openly discriminated against Christian employees, as Muslim and Hindu employees were permitted to wear headscarves and turbans.
Ms Eweida refused to comply with the firm's request that she should wear the necklace out of view underneath her uniform, accusing them of religious discrimination.
She will now have to wait a week to hear from the airline whether she can return to her old job.
British Airways has already announced a review of its policy after coming under fierce attack from church leaders and politicians.
The Archbishop of Canterbury, Dr Rowan Williams, said the airline's anti-cross stance was "deeply offensive".
"If BA is really saying or implying that the wearing of a cross in public is a source of offence, then I regard that as deeply offensive and, in a society where religious liberty and the expression of religious commitment is free, I regard it as something really quite serious."
"If they're saying that it's to do with matters of health and safety, I would question whether that is a sensible kind of regulation, whether in fact there really is a problem here, and I would ask them to look very seriously at this, given the enormous reaction of dismay that's been caused in the Christian community."
The review will look at how the rules can be adapted so symbols of faith could be worn openly. Options suggested include allowing religious symbols to be worn as small lapel badges.
BA chief executive Willie Walsh dismissed accusations that the company was anti-Christian but said the debate had forced a review of the policy.
"Our current policy has served us well, and though it is consistent with that of many other airlines, it has become clear that the policy will need to change in the light of the public debate," Mr Walsh added.
Miss Eweida said she was "dubious" about the review. "If Christians are wearing crosses they should be asked what they want to wear," she said.
"Lapel badges are generally for men, females like wearing chains with crosses on them. The lapel badge has to be dignified and respectable.
"I'm concerned it might not go far enough, Christians should have the freedom to wear the cross as we want, not on a jacket which gets taken off.
"There was no compromise for other religions about how they wear the bangal, hijab or turban - Christians should be respected."
