We aimed to describe 1) the burden and HRQL of informal caregivers of new patients attending a memory assessment service (MAS), 2) changes in these outcomes over two years and 3) satisfaction with services. Informal caregivers of patients attending one of 73 MASs throughout England completed questionnaires at the patient's first appointment, and 6 and 12 months later. Participants from 30 of these MASs were also followed up at 24 months. Questionnaires covered caregivers' sociodemographic characteristics, Zarit Burden Interview, EQ-5D-3L and satisfaction with services. We used multivariable linear regression to assess relationships between burden, HRQL and caregiver and patient characteristics. Of 1020 caregivers at baseline, 569 were followed up at 6 months, 452 at 12 months and 187 at 24 months. There was a small increase in caregiver burden over two years (effect size 0.30 SD). These changes were not associated with most caregiver or patient characteristics, except socioeconomic deprivation which was associated with larger increases in burden at two years. Caregivers' HRQL was weakly associated with burden and showed a small reduction over time (0.2 SD). Most caregivers were satisfied with services but caregivers who were not satisfied with the services they received reported greater increases in burden. Increases in caregiver burden and reductions in HRQL appear to be small over the first two years after attending a MAS. However, the longer-term impact on caregivers and those they care for needs investigating, as do strategies to reduce their burden.