Introduction There has been an almost 100% increase in referrals to breast cancer diagnostic clinics in the past decade. Breaching of the two-week cancer referral target is now commonplace, potentially delaying diagnoses of breast malignancy in many women. Almost one in five of these referrals are women with mastalgia, not a symptom linked to breast cancer. The objective of the study was the safe introduction of an advanced nurse practitioner-led telephone service for women with mastalgia to improve the service for women and create capacity for those with “red flag” breast symptoms. Methods Referrals to clinic were triaged, women with mastalgia only were directed to a telephone-based assessment clinic and symptoms evaluated using a multidisciplinary created proforma. Results Within 23 months, 1,427 women were assessed in the breast pain telephone assessment clinic: 863 (61%) were aged over 40 and 564 (39%) aged under 40. A total of 1,238 underwent telephone assessment. Reassurance and discharge only was needed for 365 (26%). The aetiology of pain was identified as musculoskeletal in 1,104/1,238 (89%) of patients, with only 39/1,238 (3.2%) identified as having true breast pain. Additional symptoms were mentioned by 264 women (18%) during the consultation; all immediately redirected back to a diagnostic clinic. Mammography was undertaken in 609 women (43%). Seven women (0.6%) were diagnosed with a breast malignancy. Patient survey indicated that 93% of patients were satisfied with the care received and 97% said they would recommend the service to a family member or friend. Conclusions Although face-to-face assessments for breast pain remain the standard practice in many breast units, data indicating the safety of a telephone assessment clinic, along with high levels of patient satisfaction, question whether services can be delivered differently.