  Form factors of the stress-tensor multiplet operator in $\mathcal{N}=4$
supersymmetric Yang-Mills reveal surprisingly simple structures similar to
those appearing in scattering amplitudes. In this paper we show that, as for
the case of amplitudes, they also enjoy dual conformal symmetry. We compute the
dual conformal anomaly at one loop for an arbitrary number of particles and
generic helicities, which matches the expression of the dual conformal anomaly
of amplitudes, and perform explicit checks for MHV and NMHV one-loop form
factors. In the NMHV case the realisation of dual conformal symmetry requires a
delicate cancellation of offending terms arising from three-mass triangles,
which we explicitly check in the case of the four-point NMHV form factor.
