INTRODUCTION: In the absence of a vaccination programme, the coronavirus disease 2019 (COVID-19) pandemic had substantial impacts on population health and wellbeing and health care services. We explored the association between COVID-19 status, sociodemographic, socioeconomic and clinical factors and economic costs during the second wave of the COVID-19 pandemic. DATA: The study used patient-reported digital survey and symptom surveillance data collected between July and December 2020, in collaboration with a primary care computerised medical record system supplier, EMIS Health, in the UK. The study included 11,534 participants. METHODS: Generalised linear models (GLM) and two-part regression models were used to estimate factors associated with economic costs (£sterling, 2022 prices) estimated from two perspectives: (i) a UK National Health Service (NHS) and personal social services (PSS) perspective and (ii) a societal perspective. RESULTS: Experience of the onset of COVID-19 symptoms started more than 3 months ago was associated with significantly higher NHS and PSS costs (GLM: £319.8, two-part: £171.7) (p <
0.001) and societal costs (GLM: £776.9, two-part: £675.6) (p <
0.001) in both models. A positive test result within the previous 14 days was associated with significantly higher NHS and PSS costs (two-part: £389.1) (p <
0.05) and societal costs (GLM: £470.7, two-part: £439.2) (p <
0.01). Age between 31 and 55 years was associated with significantly higher societal costs than age between 16 and 30 years. CONCLUSION: This study identifies and quantifies factors associated with the economic costs incurred during the second wave of the COVID-19 pandemic in the UK. The results of our study can inform cross-country comparisons and other cost comparisons.