  We set out to look at the overlap between CHEOPS sky coverage and TESS
primary mission monotransits to determine what fraction of TESS monotransits
may be observed by CHEOPS. We carry out a simulation of TESS transits based on
the stellar population in TICv8 in the primary TESS mission. We then select the
monotransiting candidates and determine their CHEOPS observing potential. We
find that TESS will discover approximately 433 monotransits during its primary
mission. Using a baseline observing efficiency of 40% we then find that 387 of
these ($\sim$89%) will be observable by CHEOPS with an average observing time
of $\sim$60 days per year. Based on the individual observing times and orbital
periods of each system we predict that CHEOPS could observe additional transits
for approximately 302 of the 433 TESS primary mission monotransits ($\sim$70%).
Given that CHEOPS will require some estimate of period before observing a
target we estimate that up to 250 ($\sim$58%) TESS primary mission monotransits
could have solved periods prior to CHEOPS observations using a combination of
photometry and spectroscopy.
