Life Cycle Assessment (LCA) methods for land use take both occupation and transformation impacts into account. However, for wetlands and impacts from water consumption, it is so far not possible to account for transformation impacts. It is our goal to close this research gap, by determining wetland recovery times and developing characterization factors for transformation. To do this, we conducted a meta-analysis of 59 studies analyzing biodiversity recovery in wetlands subject to passive and active restoration. Generalized linear models were fitted to the biodiversity data and age, along with other wetland characteristics (such as elevation, latitude, or climate class), and were used as predictor variables. The results indicate that elevation, latitude, type of wetland, and restoration method have the strongest effect on recovery speed. Recovery times vary from less than one year to a maximum of 107 years with passive restoration and 105 years with active restoration. Corresponding transformation characterization factors vary between 10-14 and 10-2 species-eq·year2/m3. Finally, recognizing the relevance of this work to real-world policy issues beyond LCA, we discuss the implications of our estimated restoration times on the feasibility of "biodiversity offsetting". Offsetting utilizes restoration to replace biodiversity value lost due to development impacts. Our work can help stakeholders make informed decisions on whether offsetting represents a legitimate policy option in a particular context.