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Abstract We revisit light-cone sum rules with pion distribution amplitudes to determine the full set of local B ¯ $$ \overline{B} $$ → π form factors. To this end, we determine all duality threshold parameters from a Bayesian fit for the first time. Our results, obtained at small momentum transfer q 2, are extrapolated to large q 2 where they agree with precise lattice QCD results. We find that a modification to the commonly used BCL parametrization is crucial to interpolate the scalar form factor between the two q 2 regions. We provide numerical results for the form factor parameters — including their covariance — based on simultaneous fit of all three form factors to both the sum rule and lattice QCD results. Our predictions for the form factors agree well with measurements of the q 2 spectrum of the semileptonic decay B ¯ 0 → π + ℓ − ν ¯ ℓ $$ {\overline{B}}^0\to {\pi}^{+}{\mathrm{\ell}}^{-}{\overline{\nu}}_{\mathrm{\ell}} $$ . From the world average of the latter we obtain |V ub | = (3.77 ± 0.15) · 10 −3, which is in agreement with the most recent inclusive determination at the 1 σ level.