A scalable, multiplexed ion trap for quantum information processing is fabricated and tested. The trap design and fabrication process are optimized for scalability to small trap size and large numbers of interconnected traps, and for integration of control electronics and optics. Multiple traps with similar designs are tested with $^{111}$Cd$^+$, $^{25}$Mg$^+$, and $^{88}$Sr$^{+}$ ions at room temperature and with $^{88}$Sr$^+$ at 6 K, with respective ion lifetimes of 90 s, 300 $±$ 30 s, 56 $±$ 6 s, and 4.5 $±$ 1.1 hours. The motional heating rate for $^{25}$Mg$^{+}$ at room temperature and a trap frequency of 1.6 MHz is measured to be 7 $±$ 3 quanta per millisecond. For $^{88}$Sr$^{+}$ at 6 K and 540 kHz the heating rate is measured to be 220 $±$ 30 quanta per second.