Tent caterpillars are generalists across their full host range, but display local host plant preferences. We present evidence for a new host plant record, wax currant (Ribes cereum), for western tent caterpillars (Malacosoma californicum) along the Colorado Front Range. We tested the suitability of wax currant as a host plant for western tent caterpillars as compared to chokecherry (Prunus virginiana), an abundant and commonly used host plant. We measured the density of tent caterpillar tents in areas where both host plants occur to assess host plant use. We reared tent caterpillar larvae on both host plants and measured fitness effects due to host plant quality (survival, pupal mass) and natural enemies (parasitism). We did not find a relationship between host plant abundance and use by tent caterpillars and found no evidence for a preference for either host plant. We found that western tent caterpillars do not differ in pupal mass when reared on chokecherry and on wax currant in a laboratory setting, but did vary in survival with greater survival on wax currant. We found no difference in parasitism rate for larvae collected from chokecherry or wax currant. Our results suggest that wax currant is a suitable yet previously unrecorded host plant for tent caterpillar larvae.