Two regulators signed off on the $35 billion deal, which the banks say will create a competitor to Visa and Mastercard. But consumer advocates warn that the deal may raise costs.

The all-stock deal, first announced over a year ago, would give Capital One a major leg up against competing credit card-issuing banks such as JPMorgan Chase ( JPM ), Bank of America ( BAC) and Citigroup ( C ), which don’t process transactions themselves.

Capital One Financial’s application to acquire Discover Financial Services in a $35.3 billion all-stock deal has officially been approved by the Federal Reserve and the Office of the Comptroller of the Currency,