International payments startup Flywire has made its fourth acquisition, bringing the Boston-based company’s global headcount to roughly 250.

The company announced on Thursday that it acquired OnPlan Holdings, the Chicago-area parent company of OnPlanU and OnPlan Health, which provide payments solutions for higher education institutions and healthcare organizations, respectively.

Flywire, which has raised a total of $43 million from investors, has acquired PACE Invoice, ScholarFX and Uni-Pay over the past three years to build out its capabilities as an international payments servicer in the education, healthcare and business sectors.

With the acquisition of OnPlan, the company said it is now “the first in the industry” to provide an end-to-end international payments solution, which includes invoicing, secure payment processing, consumer engagement and automated payment plans, among other capabilities.

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A Flywire spokeswoman said all 20 of OnPlan employees will join Flywire’s team and continue to work from its office outside of Chicago. OnPlan’s co-founders, CEO John Talaga and CTO David King, will join Flywire’s leadership team, with Talaga leading Flywire’s healthcare division and King leading the company’s education and healthcare-focused product and development teams.

“The addition of OnPlan solidifies our market leadership position by enabling us to go deeper to address specific client needs in education and healthcare, and giving our clients the ability to manage all payments and receivables from a single platform,” Mike Massaro, CEO of Flywire, said in a statement. “Our clients have been pushing us for this, and the OnPlan team brings a tremendous amount of technical capability and domain expertise to address it.”