To spread the word about the balance transfer deal, Tower said it used direct mail, direct e-mail, and statement inserts along with other approaches across other media and channels.

Tower said one key difference between 2013 and 2014's promotions was the addition of a recapture program this year.

Working in partnership with TransUnion, the recapture effort involved targeted marketing to more than 36,000 Tower members, according to the credit union.

TransUnion selected the members based on creditworthiness and if they had a credit card with another financial institution. The target group received a letter from Tower that touted the balance transfer offer and the benefits of a Tower MasterCard.

The letters were followed up with phone calls by branch and member service personnel, Tower said.

The letters and calls netted over $2.6 million in transferred balances, which was nearly half of all the balances transferred during the April to August promotional period, according to Tower.

The follow-up phone calls were key to the recapture program's success, Jackie McMannis, Tower's product planner on lending, said.

“Members who received a follow-up phone call after the mailing had a significantly higher response to the promotion than those who received only the mailing,” she said.

“Our members appreciated the personal touch of a phone call and realized the savings and value of transferring their high-rate balances to a Tower MasterCard for a lower interest rate and no transfer fees,” McMannis added.