Apparatus containing micro-or minichannels are seen as promising tools to intensify several chemical engineering processes. For gas−liquid systems, the apparatus should operate in the Taylor flow regime due to its excellent mass transfer coefficients and low back-mixing. The presence of the regime depends on several geometric and operational parameters as well as material properties. To the best knowledge of the authors, the available information stored in flow maps for specific conditions has never been generalized. This work presents novel decision trees that enable the boundaries of Taylor flow in minichannels to be predicted, which are based on the data of 97 different flow maps covering a broad range of configurations. The developed criteria are mathematical functions that describe the transitions from Taylor to bubbly flow, Taylor−annular flow, or churn flow. These functions involve 7 dimensionless groups, namely u G,s /u L,s , μ G /μ L , ρ G /ρ L , Re L , We L , Θ*, and, a channel form factor, R A .