One of the Buffalo Bills’ most reliable players over the last four seasons is now a former member of the team.

Just minutes after the start of the NFL free-agency period Tuesday afternoon, guard Andy Levitre agreed to a contract with the Tennessee Titans, according to several media reports, the first of which came from ESPN’s Adam Schefter.

The Tennessean reported the deal to be for six years and worth up to $46.8 million, a massive investment.

The average yearly salary of $7.8 million makes Levitre the fourth-highest paid guard in the NFL behind Tampa Bay’s Carl Nicks ($9.5 million), New England’s Logan Mankins ($8.5 million) and New Orleans’ Jahri Evans ($8.1 million).

A 2009 second-round draft pick, Levitre, 27, started all 64 games he played for the Bills. Over the last 46 games, he didn’t missed a single snap.

The Bills, however, had not presented a contract offer to Levitre as of the start of this month.

“It’s an exciting time for me, being able to have this opportunity,” Levitre told The News earlier this month. “This position that I’m in, it’s once-in-a-lifetime for a lot of people. I don’t know if this’ll ever happen to me again.

“It would be in the Bills’ best interests to at least throw me an offer to see if we can get this thing rolling. There’s a lot of unknown for me.”

Whether the Bills eventually did make an offer to Levitre is not known.

He did not return a call from The News on Tuesday.

The Bills have another unrestricted free agent guard in Chad Rinehart, and have to be mindful of the fact center Eric Wood is entering the final year of his contract.

They re-signed guard Kraig Urbik last season to a four-deal that could pay him as much as $15 million.

While durable, Levitre has never made a Pro Bowl or All-Pro team in his professional career.

Guards do not usually collect big salaries compared to tackles on the offensive line, but the Titans deemed Levitre worthy of an exception to that rule.

Tennessee gave up 39 sacks last season, 12th most in the NFL, and ranked just 21st in rushing with former 2,000-yard runner Chris Johnson.

The 6-foot-2, 305-pounder came to Buffalo as the 51st overall selection in 2009 out of Oregon State.

He was the Bills’ highest-rated offensive lineman, according to advanced statistics compiled by the website Pro Football Focus, with a positive rating of 17.3. Levitre graded out much higher in his pass blocking, at 15.7, than he did in his run blocking (-0.7).

Bills General Manager Buddy Nix was asked about re-signing Levitre at last month’s NFL Scouting Combine.

“It’s important for us to keep all three of those guys,” Nix said, referring to Levitre, safety Jairus Byrd (who was given the franchise tag) and cornerback Leodis McKelvin (who was re-signed). “It’s the nature of the business. Sometimes you can’t keep them all. We’ll try. We’ll try to see what a guy’s value is to us and then we stick to that. If his value is more to somebody else, good luck for him and good for him.”