  The LIGO and Virgo Collaborations currently conduct searches for
gravitational waves from compact binary coalescences in real-time. For
promising candidate events, a sky map and distance estimation are released in
low-latency, to facilitate their electromagnetic follow-up. Currently, no
information is released about the masses of the compact objects. Recently,
Margalit and Metzger (2019) have suggested that knowledge of the chirp mass of
the detected binary neutron stars could be useful to prioritize the
electromagnetic follow-up effort, and have urged the LIGO-Virgo collaboration
to release chirp mass information in low-latency. One might worry that
low-latency searches for compact binaries make simplifying assumptions that
could introduce biases in the mass parameters: neutron stars are treated as
point particles with dimensionless spins below $0.05$ and perfectly aligned
with the orbital angular momentum. Furthermore, the template bank used to
search for them has a finite resolution. In this paper we show that none of
these limitations can introduce chirp mass biases larger than $\sim
10^{-3}~M_\odot$. Even the total mass is usually accurately estimated, with
biases smaller than 6%. The mass ratio and effective inspiral spins, on the
other hand, can suffer from more severe biases.
