Engaging patients in a group-based weight loss program is a challenge for the acute-care hospital outpatient setting. To evaluate the feasibility, effectiveness and costeffectiveness of a telephone-based weight loss service and an existing face-to-face, group-based service a nonrandomised, two-arm feasibility trial was used. Patients who declined a two-month existing outpatient groupbased program were offered a six-month research-based telephone program. Outcomes were assessed at baseline, two months (both groups) and six months (telephone program only) using paired t tests and linear regression models. Cost per healthy life year gained was calculated for both programs. The telephone program achieved significant weight loss (−4.1±5.0 %; p=0.001) for completers (n=35; 57 % of enrolees) at six months. Compared to the group-based program (n=33 completers; 66 %), the telephone program was associated with greater weight loss (mean difference [95%CI] −2.0 % [−3.4, −0.6]; p=0.007) at two months. The cost per healthy life year gained was $33,000 and $85,000, for the telephone and group program, respectively. Telephonedelivered weight management services may be effective and cost-effective within an acute-care hospital setting, likely more so than usual (group-based) care.