The chromatin remodelling factor chromodomain helicase DNA‐binding protein 4 (CHD4) is a catalytic subunit of the NuRD transcriptional repressor complex. Here, we reveal novel functions for CHD4 in the DNA‐damage response (DDR) and cell‐cycle control. We show that CHD4 mediates rapid poly(ADP‐ribose)‐dependent recruitment of the NuRD complex to DNA‐damage sites, and we identify CHD4 as a phosphorylation target for the apical DDR kinase ataxia‐telangiectasia mutated. Functionally, we show that CHD4 promotes repair of DNA double‐strand breaks and cell survival after DNA damage. In addition, we show that CHD4 acts as an important regulator of the G1/S cell‐cycle transition by controlling p53 deacetylation. These results provide new insights into how the chromatin remodelling complex NuRD contributes to maintaining genome stability.