  Supermassive black hole binaries are promising sources of low-frequency
gravitational waves (GWs) and bright electromagnetic emission. Pulsar timing
array searches for resolved binaries are complex and computationally expensive
and so far limited to only a few sources. We present an efficient approximation
that empowers large-scale targeted multi-messenger searches by neglecting GW
signal components from the pulsar term. This Earth-term approximation provides
similar constraints on the total mass and GW frequency of the binary, yet is
$>100$ times more efficient.
