PlayStation 2 will need an adaptor for online services
Sony said it will sell a network adapter for $39.99 (£28) beginning that month, allowing for both low and high-speed Internet connections.
The PS2 does not have built-in network capabilities but does have high-speed expansion ports designed for such a purpose.
It is the latest in the battle of the gaming consoles as Sony takes on Microsoft's Xbox and the GameCube from Nintendo.
Last month Sony said online gaming would be a reality in Japan in April.
PlayStation BB will also give users access to internet browsing, e-mail and instant messaging services, mp3 music file access and video streams.
However Mike Wallace, an analyst at UBS Warburg, said he is not confident of online gaming success for Sony in the US.
He said: "Peripherals and add-ons do not do well in this industry. No-one's going to spend a lot of money (on this).
"First of all because it's not apparent how any of the third parties are going to make any money on this, and second of all, there's no installed base."
By third parties, Mr Wallace was referring to video game publishers, like Electronic Arts, who have experience in developing online games for consoles and the PC.
No games were announced for the new platform, though Sony said it would reveal them in the coming months.
Microsoft's Xbox has the advantage over its rivals when it comes to online gaming because it will not need any additional adaptors.
Competition
The company is rolling out its new services later this year.
However the Xbox is more expensive than both the PS2 and GameCube.
Nintendo has kept quiet so far on the online gaming potential of their GameCube, as it has no built-in access ports.
Both the GameCube and Xbox have yet to be launched in Europe.
Microsoft's games console comes onto the market on 14 March, while Nintendo's machine is released in May.