Private equity firm the Riverside Co. has made another add-on deal for Paradigm Tax Group.

The firm bought Pence & Associates, headquartered in Kansas City, Mo., to strengthen the tax group's Midwest presence. Terms of the deal were not disclosed.

Paradigm, based in Phoenix, provides tax consulting services for commercial property owners through more than 30 offices in the U.S. The company analyzes property portfolios to look for ways to save on taxes.

Riverside invested in Paradigm in November. In January, Riverside bought AVS Tax Inc. and Hart Property Consultants as add-on acquisitions for Paradigm. 

The firm bought Paradigm from its recently-closed $1.5 billion fund. Riverside won Mergers & Acquisitions Private Equity Firm of the Year award for 2012, after completing its 300th transaction.