The team announced the finalized purchase in an open letter, though they did not disclose the final purchase price. It was previously reported the team had agreed to pay nearly $200 million for the 326 acres in the northwest suburbs.
The Bears have announced plans to build an enclosed stadium and multi-purpose entertainment district on the land, but cautioned in their open letter that the purchase does not guarantee that in and of itself.
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"Finalizing the purchase does not guarantee the land will be developed, but it is an important next step in our ongoing evaluation of the opportunity. There is still a tremendous amount of due diligence work to be done to determine if constructing an enclosed state-of-the-art stadium and multi-purpose entertainment district is feasible," the team wrote.
"There's many, many stakeholders involved in this process as we found out over the last year and a half, but this is a major milestone along the way. We know there's a long, long way to go, so I'm reasonably confident that we're going to be able to get this thing done," said Arlington Heights Mayor Tom Hayes.
Will Bears closng on Arlington Heights property impact Mayor Lightfoot's re-election effort?
Will Bears closng on Arlington Heights property impact Mayor Lightfoot's re-election effort?
The mayor hailed the news, which came almost a year and a half after the initial sale.
"There are a number of ways that the project could conceivably be derailed, but this is a locomotive moving down the tracks," said Marc Ganis of Sportscorp.
Residents of Arlington Heights have expressed concerns about how the stadium will be paid for and the effects on their taxes. Arlington Heights trustees unanimously rejected a petition signed by residents that sought to keep the Bears from receiving any public money for the mixed-use development around the stadium. The team has said they will not seek tax dollars to build the stadium itself.
The team reiterated its desire for property tax certainty. There's currently a bill in Springfield, which some object to, that would freeze the assessed value of the property for four decades.
"The Bears don't need tax subsidies. If they have a viable project, they shouldn't need tax subsidies. They are either saying one of two things: one, they need tax subsidies because their project is fundamentally bankrupt, or two, they're just trying to pad their profit," said Brian Costin of Americans for Prosperity Illinois.
"We want this to be a win-win for everybody, and so we're doing all we can, and the Bears are doing all we can to make everybody's best interests are protected," said Hayes.
In an effort to keep the team at Soldier Field, the city recently released proposals to renovate their current home, adding a dome and expanding seating, among other changes. The Bears appeared to be unswayed by the offer.
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Mayor Lori Lightfoot's office released a statement after the open letter was released, saying in part, "Today's news about the closure of the Bears' option in Arlington Heights has been anticipated for some time. Nonetheless, all of us die-hard Bears fans, the Mayor included, know and believe that the Chicago Bears should remain in Chicago. So, now that the land deal has closed, we have an even better opportunity to continue making the business case as to why the Bears should remain in Chicago and why adaptations to Solider Field can meet and exceed all of the Bears' future needs."
READ MORE: Arlington Heights rejects petition to ban public money for Chicago Bears development
The mayor's office said it can now officially negotiate with the team, saying prior to this closing the Bears were legally barred from talking to the city