Purpose. Evaluate total annual costs [TAC] associated with management of asthma and comorbid allergic rhinitis [A+AR] among patients treated with either montelukast [MON] or long acting beta agonists [LABA] added to inhaled corticosteroids [ICS] in France. Methods. A cost minimization analysis based model using 3rd party payer's perspective was developed. TAC per patient included asthma controller acquisition cost [ACAC], A+AR related concomitant drug cost [AAR-COST] (incl. allergy, rescue/acute and other asthma medications) and asthma-related medical resource use [A-MRU] cost (incl. unscheduled physician visits, ER visits, hospitalizations). ACAC were calculated using published daily cost, observed and published dosing and compliance. The latter included average prescription [Rx] duration and % of compliant patients. AAR-COST were derived from a French observational study and A-MRU cost from a randomized clinical trial along with published unit costs. A deterministic sensitivity analysis (SA) for ACAC varied the average Rx duration [range 30-100% including the observed rate] and dosing (indicated-Vidal, observed-IMS). AAR-COST, A-MRU and TAC underwent a probabilistic sensitivity analysis using 2nd order Monte Carlo simulation (500 iterations). Results. Base case. Treatment of A+AR patients with ICS+MON vs ICS+LABA results in similar AAR-COST [€137 for ICS+MON vs. €137 for ICS+LABA] and similar A-MRU cost [€152 vs. €132]. These two costs combined were €288 for ICS+MON vs. €269 for ICS+LABA. ACAC was €120 for ICS+MON vs. €121 for ICS+LABA using observed compliance rate, and €306 vs. €322 with 100% compliance. TAC per patient was €409/€594 in the ICS+MON group and at €390/€592 in the ICS+LABA group for observed/100% compliance rates respectively. None of the estimates were statistically different between groups. Conclusion. Total annual cost per patient with asthma+AR is similar among patients treated with ICS+MON compared to patients using ICS+LABA. Multiple sensitivity analyses demonstrate that these conclusions are robust.