BackgroundThe COVID-19 pandemic has upended graduate medical education globally. We investigated the COVID-19 impact on learning inputs and expected learning outputs of plastic surgery residents across the world.MethodsWe administered an online survey capturing training inputs before and during the pandemic and retrieved residents’ expected learning outputs compared with residents who completed their training before COVID. The questionnaire reached residents across the world through the mobilization of national and international societies of plastic surgeons.ResultsThe analysis included 412 plastic surgery residents from 47 countries. The results revealed a 44% decline (ranging from − 79 to 10% across countries) and an 18% decline (ranging from − 76 to across 151% countries) in surgeries and seminars, respectively, per week. Moreover, 74% (ranging from 0 to 100% across countries) and 43% (ranging from 0 to 100% across countries) of residents expected a negative COVID-19 impact on their surgical skill and scientific knowledge, respectively. We found strong correlations only between corresponding input and output: surgeries scrubbed in with surgical skill (ρ=−0.511 withp <0.001) and seminars attended with scientific knowledge (ρ= − 0.274 withp= 0.006).ConclusionsOur ranking of countries based on their COVID-19 impacts provides benchmarks for national strategies of learning recovery. Remedial measures that target surgical skill may be more needed than those targeting scientific knowledge. Our finding of limited substitutability of inputs in training suggests that it may be challenging to make up for lost operating room time with more seminars. Our results support the need for flexible training models and competency-based advancement.Level of evidence VThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authorshttp://www.springer.com/00266.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00266-023-03389-w.