BACKGROUND: Multiple drug treatments are approved for invasive breast cancer (IBC). We investigated uptake of NICE-recommended oncological drugs and variation by age, comorbidity burden and geographical region. METHODS: Women (aged 50+ years) diagnosed with IBC from 2014 to 2019, were identified from England Cancer Registry data and drug utilisation from Systemic Anti-Cancer Therapy data. Interrupted time series analysis assessed national-level changes in drug use after publication of NICE recommendations. Regression models analysed variation in use. RESULTS: This national cohort included 168,449 women. Use of drugs recommended for first-line treatment varied, from 26.6% for CDK 4/6 inhibitors to 63.8% for HER2-targeting therapies. Utilisation of drugs with a NICE recommendation published between 2014 and 2019, increased among patients diagnosed around the time of publication, except in the case of pertuzumab for metastatic breast cancer (MBC) which was previously accessible via the Cancer Drugs Fund (though use of pertuzumab for MBC increased from 34.1% to 75.0% across the study period). Use of trastuzumab and neoadjuvant/adjuvant pertuzumab varied by geographical region. Use was low for ribociclib (2.2%), abemaciclib (2.3%) and for drugs recommended beyond the first-line setting. For all drugs, use after NICE recommendation varied by age at diagnosis and increased as stage increased. CONCLUSIONS: Use of NICE-recommended drugs for IBC in routine care is variable, with lowest use among women aged 70+ years. Improving access to effective treatments is an important step in improving outcomes.