The TJX Cos. is considering relocating from its 780,000-square-foot Framingham headquarters, according to several reliable sources familiar with the discount retailer’s potential plans.

The parent company of retailers T.J. Maxx, Marshalls and others, TJX is currently in the market, kicking the tires on options available for its large requirements, sources say.

"TJX is looking for something big," said one commercial broker knowledgeable about the possible move or expansion. "What will happen in the end, no one is exactly sure. But we know that whatever they want, it’s going to be big."

The company’s motivation for hitting the streets for new space stems from its IT group in Westborough, which is in expansion mode and whose lease expires in the next couple of years. That upcoming expiration is making the company step back to take a long, hard look at its real estate needs.

TJX occupies nearly 1.3 million square feet of office space between its headquarters and properties in Westborough, all of which is leased. But there are few contiguous options for a requirement of that size.

Average Class A asking rents in the Framingham/Natick area are at about $26.40 per square-foot right now, according to information from Richard Barry Joyce & Partners.

The first two of TJX’s three interconnected buildings in Framingham were erected in 1989 and 1990, with the third coming online in 2001. The first two portions are already more than 20 years old, and likely in need of upgrades to the mechanical, electrical and plumbing systems, as well as the roofs, though "they’re probably not leaking yet," said one source familiar with the properties.