INTRODUCTION: South Africa is the HIV epidemic epicentre; however, non-communicable diseases (NCDs) will be the most common cause of death by 2030. To improve identification and initiation of care for HIV and NCDs, we assessed proportion of clients referred and linked to care (LTC) for abnormal/positive screening results and time to LTC and treatment initiation from a HIV Testing Services (HTS) Centre before and after integrated testing for NCDs with optional peer-navigated linkage to care. MATERIALS AND METHODS: This two-phase prospective study was conducted at an adult HTS Centre in Soweto, South Africa. Phase 1 (February-June 2018) utilised standard of care (SOC) HTS services (blood pressure [BP], HIV rapid diagnostic testing (RDT), sexually transmitted infections [STI]/Tuberculosis [TB] symptom screening) with passive referral for abnormal/positive results. Phase 2 (June 2018-March 2019) further integrated blood glucose/cholesterol/chlamydia RDT, with optional peer-navigated referral. Enrolled referred clients completed telephonic follow-up surveys confirming LTC/treatment initiation </=3 months post-screening. Socio-demographics, screening results, time to LTC/treatment initiation, peer-navigated referral uptake were reported. Analysis included Fisher's exact, chi-squared, Kruskal Wallis, and Student's T-tests. Thematic analysis was conducted for open-ended survey responses. RESULTS: Of all 320 referrals, 40.0% were HIV-infections, 11.9% STIs, 6.6% TB, and 28.8% high/low BP. Of Phase 2-only referrals, 29.4% were for glucose and 23.5% cholesterol. Integrated NCD-HTS had significantly more clients LTC for HIV (76.7%[n = 66/86] vs 52.4%[n = 22/42], p = 0.0052) and within a shorter average time (6-8 days [Interquartile range (IQR):1-18.5] vs 8-13 days [IQR:2-32]) as compared to SOC HTS. Integrated NCD-HTS clients initiated HIV/STIs/BP treatment on average more quickly as compared to SOC HTS (5 days for STIs [IQR:1-21], 8 days for HIV/BP [IQR:5-17 and 2-13, respectively] vs 10 days for STIs [IQR: 4-32], 19.5 days for HIV [IQR:6.5-26.5], 8 days for BP [IQR:2-29)]. Participants chose passive over active referral (89.1% vs 10.9%; p<0.0001). Participants rejecting peer-navigated referral preferred to go alone (55.7% [n = 39/70]). Non-LTC was due to being busy (41.1% [n = 39/95]) and not being ready/refusing treatment (31.6% [n = 30/95]). Normalised results assessed at referral clinic (49.7% [n = 98/196]), prescribed lifestyle modification/monitoring (30.9% [n = 61/196]), and poor clinic flow/congestion and/or further testing required (10.7% [n = 21/196]) were associated with non-treatment initiation. CONCLUSION: Same-day treatment initiation is not achieved across diseases, despite peer-navigated referral. There are psychosocial and health systems barriers at entry to care/treatment initiation. Additional research may identify best strategies for rapid treatment initiation.