Delaying or refraining from seeking advice and support in difficult parenting situations is identified as an important risk factor for child abuse and neglect. This study tested whether the extent of delays in support seeking is associated with working alliance for parents with mild intellectual disabilities (MID) and whether the importance of working alliance may depend on parenting stress and availability of informal support. Delays in support seeking were measured as parental latency (time waited) to approach the support worker. This latency was assessed in the intended response to hypothetical situations (vignettes) and in the reported behavioral response to real life difficult parenting situations from the preceding weeks. Multiple regression analyses were conducted for testing main and interaction effects of predictors on latency for support seeking. Better quality of the working alliance was associated with shorter intended latency to seek support for parents with MID, if parents had little access to informal support. Higher parenting stress predicted a shorter latency for intended support seeking. Parental support seeking intentions were positively associated with support seeking behavior. A good quality of the working alliance might be important to connect needs of parents with MID to resources that professional support can offer, in particular for the most vulnerable parents. Parental reluctance to seek professional support may be the result of a combination of risk and protective factors and is not always a sign of poor working alliance. Implications for risk assessment and support practice are discussed.