The company, which hunts for oil and gas in the Middle East and southern Africa, said the funds will go towards exploration work at its assets in Oman, as well as working capital.
It had previously highlighted raising £20mln in the IPO, which was initially scheduled for March.
“The company is seeking admission to AIM in order to take advantage of the market's higher profile, broader investor base, liquidity and access to institutional investors,” a stock exchange statement read.
“The directors believe that the admission should provide liquidity for current and future investors in the company and provide the company with the flexibility to issue new shares as consideration for any acquisition.”
The company thinks the time is right for the move, citing significant progress made of late.
It signed the Oman exploration and production sharing agreement (EPSA) in October and disposed of its US production assets the following month.
Frontier now has three exploration projects in Oman, Namibia and Zambia.