Background: Neck pain and forward head posture are common in prolonged smartphone users and need to be targeted for treatment. We aimed to compare the effect of adding respiratory exercises to the therapeutic routine in smartphone users with forward-head posture and non-specific chronic neck pain.Mehods: Sixty patients (aged 24.7±2.1 years), were randomly assigned to the therapeutic routine (n=20), combined respiratory-exercises with therapeutic routine (n=20), or control groups (n=20). Each programme was implemented three times a week for 8 weeks. Forward head angle, pain, electromyographic activity, and respiratory patterns were measured at baseline and at 8-weeks’ post-treatment. Results: There were significant improvements in the combined group compared with the therapeutic routine group (p=0.03) for diaphragm muscle activation, (p=0.03), neck erector spinae activity (p=0.04), respiratory balance (p=0.04), and number of breaths (p=0.02). There were significant within-group changes from baseline to post-treatment in the combined group for all outcomes above, but no changes in the therapeutic exercise routine group. Outcomes for the combined group were superior to the control group in every variable. Conclusion: Combination treatment is more effective than the standard therapeutic routine. These results could be strengthened by more studies with longer follow-up assessments.Trial registration: Current Controlled Trials using the IRCT website with ID number of, IRCT20200212046469N1 “Prospectively registered” at 2020/03/04.