Eighteen former First Niagara Bank branches are opening up Monday under a new name.

Northwest Bank bought those branches for $78 million. Northwest acquired the 18 branches in Erie and Niagara counties because KeyBank had to sell them off as part of its acquisition of First Niagara.

The transition saw many customers hurrying to tie up loose ends Friday, when First Niagara bank cards were deactivated. Northwest has promised a seamless transition, but some complications were reported by customers Friday and over the weekend.

Financial Guys President Michael Lomas said to stay on top of your accounts while the bank is going through the transition.

"First of all, start to open up some of your statements. Unfortunately a lot of people don't do that - 'Ah, my bank account is fine. I go online.' Start to recognize and understand what the fees are now during that transition, and what the fees are going to be. Maybe I paid $5 for my checking account, now it's $20. You need to know that. What's attached to the deal?" he said.

Customers with direct deposits will have several weeks to switch those deposits to their Northwest accounts, which have different account numbers. Officials with Northwest  said they know there will be questions and have added staff to their customer service center to deal with high call volumes. Any customers who need help can reach a representative at (877) 672-5678.

Those First Niagara branches that weren't taken over by Northwest should to be converted to KeyBank by the end of the year.