A Sydney law firm is investigating a potential class action against Virgin Australia and Jetstar over the airlines' pricing tactics, after a November ruling that the two carriers misled consumers about ticket prices.

Last month the Federal Court found the airlines engaged in "drip pricing" – where an advertised price gets higher as a business discloses extra costs – which was misleading, deceptive and contravened consumer law.

Jetstar and Virgin may face further legal action over their pricing tactics. Credit:Louise Kennerley

Now Bannister Law says it is looking into the potential for a class action over the case, which was brought by the Australian Competition and Consumer Commission. It says the action could end up being Australia's biggest ever consumer class action if it goes ahead.

In the case, the ACCC said the airlines had failed to adequately disclose in some of their advertising a "booking and service fee," which was $8.50 for Jetstar and $7.70 for Virgin.