The least used border crossing in Nicaragua, El Espino is open 24 hours. To get there from Somoto , take one of the regular buses ($0.50) that head toward El Espino, or chip in for a cab (about $4). It’s a 40-minute ride from Somoto.
At the crossing, you first receive and fill out an immigration form at the booth next to the steel railroad crossing–style gate, then proceed 100 meters up to the little building on the right where you’ll pay $2 to exit ($4 after hours) or $7 to enter ($9 after hours). Continuing bus service into Honduras is just over the hill and runs until 4:30 p.m.
You should not need another visa for Honduras thanks to Nicaragua’s participation in the CA-4 Border Control Agreement of 2006.