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In this paper, we report accurate  Chandra  positions for two ultraluminous X‐ray sources (ULXs): NGC 7319‐X4 at Right Ascension (RA) = 339029 17(2), Declination (Dec.) = 33974 76(2) and NGC 5474‐X1 at RA = 211248 59(3), Dec. = 53635 84(3). We perform bore‐sight corrections on the  Chandra  X‐ray satellite observations of these sources to get these accurate positions of the X‐ray sources and match these positions with archival optical data from the Wide Field Planetary Camera 2 (WFPC2) onboard the  Hubble Space Telescope . We do not find the optical counterparts; the limiting absolute magnitudes of the observations in the WFPC2 standard magnitude system are  B =−7.9,  V =−8.7 and  I =−9.3 for NGC 7319‐X4 and  U =−6.4 for NGC 5474‐X1. We report on the X‐ray spectral properties and find evidence for X‐ray variability in NGC 5474‐X1. Finally, we briefly discuss several options for the nature of these ULXs.

Accurate positions for the ultraluminous X‐ray sources NGC 7319‐X4 and NGC 5474‐X1 and limiting magnitudes for their optical counterparts