Bebo's Cafe

Loiza and Parque st. near Condado.

Local food, generous portions and fast service, always busy with locals, very inexpensive.

The service is sometimes too fast and the restaurant space too large, open and noisy.

http://www.beboscafe.com

Tasca de Yiyo

Loiza 1753, next to Taft st., just outside Condado.

Local food/Cuban, excellent  generous portions, very inexpensive.

"Arroz con Pollo a la Chorrera" a specialty moist rice with chicken is unique.

El Pescador

Dos Hermanos 178, Plaza de Santurce, just outside Condado.

Relatively inexpensive seafood in San Juan. Try the arañitas.

Small place, tight but excellent ambiance and service. Located in

Plaza del Mercado de Santurce, a lively food market with active bars at night.

Don Tello 

Cataño, in front of the Ferry terminal (used to be in la Plaza de Santurce)

Local food, good price and a view of San Juan. Try the fried Chillo with tostones (fried Snapper and platains). 

You can take the inexpensive ferry to Cataño from Old San Juan bay and it will take you right to Don Tello.