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We use arguments developed in previous work to identify a second black hole candidate associated with an M31 globular cluster (GC), Bo 144, on the basis of X‐ray spectral and timing properties. The 2002  XMM–Newton  observation of the associated X‐ray source (hereafter XBo 144) revealed behaviour that is common to all low‐mass X‐ray binaries (LMXBs) in the low‐hard state. Studies have shown that neutron star LMXBs exhibit this behaviour at 0.01–1000 keV luminosities ≤10 per cent of the Eddington limit  ( L  Edd ) . However, the unabsorbed 0.3–10 keV luminosity of XBo 144 was  ∼0.30  L  Edd   for a  1.4 M ⊙   neutron star, and the 0.01–1000 keV luminosity is expected to be ≳3–7 times higher. We therefore identify XBo 144 as a black hole candidate. Furthermore, it is the second black hole candidate to be consistent with formation via tidal capture of a main sequence donor in a GC; such systems were previously thought non‐existent, because the donor was thought to be disrupted during the capture process.

A second black hole candidate in a M31 globular cluster is identified with XMM–Newton