Tozer, 26, spent 2015-16 at Yeovil, who he joined from Northampton.
The Plymouth-born player said: "It has been a bit of a whirlwind with the deal being sorted out so quickly, but I'm delighted to get the deal done and over the line."
Newport manager Warren Feeney said: "He has experience at this level which will be a great benefit for us."
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Defensive midfielder Ben Tozer has joined League Two's Newport County on a one-year deal.