BACKGROUND: There is a lack of data and consensus concerning the most appropriate functional evaluation in clinical practice at the definitive prosthetic phase after lower limb amputation. OBJECTIVES: To determine among several selected functional tests the most pertinent to evaluate balance and prosthetic walking. STUDY DESIGN: Validation of a diagnostic procedure. METHODS: Sixty-four patients were included. Outcome measures: Timed Up and Go test, Functional Reach test (FRT), one-leg balance, tandem test, Modified Houghton Scale, Berg Balance Scale, two-minute walk test (2MW test). Correlations were assessed with the Pearson correlation coefficient and the Principal Component Analysis. Score distribution was analyzed with the Shapiro-Wilk W normality test. Receiver operating characteristic curves were drawn to identify the best predictor for the function. RESULTS: The clinical tests correlated highly with each other. Only 2MW test and FRT did not have either a floor/ceiling effect, or a bi-modal distribution. The 2MW test was the best predictor of prosthetic walking limitations (area under the curve 0.93 (0.83-0.97), the best threshold was between 130 and 150 meters), and FRT was best for balance. CONCLUSIONS: 2MW test can be proposed as the first-line clinical test. The FRT can be indicated for the specific assessment of balance disorders. Clinical relevance This validation of a clinical evaluation of balance and walking capacity after lower limb amputation may be useful in everyday practice to ensure in a simple and standardized way the follow-up of patients and adapt treatments--especially prosthetics--at the definitive prosthetic phase.