CBS has committed itself to an initial public offering of its radio division — but that doesn’t have to shut out outside buyers.

CBS Radio is expected to file a registration statement by the end of the month, the broadcaster said in a regulatory filing.

In mid-March, Chief Executive Les Moonves announced that CBS would unload the underperforming division, which features nationally syndicated host Carson Daly.

As the country’s third-largest radio group, CBS Radio recorded a 2 percent sales dip for the most recent quarter — a drag on the 10 percent increase for CBS as a whole.

Because it acquired so many assets at decades-old prices, CBS Radio is seeking a tax-effective separation.

Tax-expert Robert Willens predicted a two-part split-off — one kicked off by the sale of 20 percent of CBS Radio shares, followed by an exchange-ratio swap with CBS shares for the reminder.

This would not only deliver a tax-free IPO but accommodate eleventh-hour bids, he said.