In this study several ice cloud retrieval products that utilize active and passive A-Train measurements are evaluated using in situ data collected during the Small Particles in Cirrus (SPARTICUS) field campaign. The retrieval datasets include ice water content (IWC), effective radiusrₑ, and visible extinctionσfromCloudSatlevel-2C ice cloud property product (2C-ICE),CloudSatlevel-2B radar-visible optical depth cloud water content product (2B-CWC-RVOD), radar–lidar(DARDAR), andσfromCloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). When the discrepancies between the radar reflectivityZₑderived from 2D stereo probe (2D-S) in situ measurements andZₑmeasured by theCloudSatradar are less than 10 dBZₑ, the flight mean ratios of the retrieved IWC to the IWC estimated from in situ data are 1.12, 1.59, and 1.02, respectively for 2C-ICE, DARDAR, and 2B-CWC-RVOD. Forrₑ, the flight mean ratios are 1.05, 1.18, and 1.61, respectively. Forσ, the flight mean ratios for 2C-ICE, DARDAR, andCALIPSOare 1.03, 1.42, and 0.97, respectively. TheCloudSat2C-ICE and DARDAR retrieval products are typically in close agreement. However, the use of parameterized radar signals in ice cloud volumes that are below the detection threshold of theCloudSatradar in the 2C-ICE algorithm provides an extra constraint that leads to slightly better agreement with in situ data. The differences in assumed mass–size and area–size relations betweenCloudSat2C-ICE and DARDAR also contribute to some subtle difference between the datasets:rₑfrom the 2B-CWC-RVOD dataset is biased more than the other retrieval products and in situ measurements by about 40%. A slight low (negative) bias inCALIPSOs may be due to 5-km averaging in situations in which the cirrus layers have significant horizontal gradients inσ.