Neutrino masses and mixing: Entering the era of subpercent precision

We perform an updated global analysis of the known and unknown parameters of the standard 3ν framework as of 2025. The known oscillation parameters include three mixing angles (θ₁₂,\,θ₂₃,\,θ₁₃) and two squared mass gaps, chosen as δ m²=m²₂-m²₁>0 and Δ m²=m²₃-1/2(m²₁+m²₂), where α=sign(Δ m²) distinguishes normal ordering (NO, α=+1) from inverted ordering (IO, α=-1). With respect to our previous 2021 update, the combination of oscillation data leads to appreciably reduced uncertainties for θ₂₃, θ₁₃ and |Δ m²|. In particular, |Δ m²| is the first 3ν parameter to enter the domain of subpercent precision (0.8% at 1σ). We underline some issues about systematics, that might affect this error estimate. Concerning oscillation unknowns, we find a relatively weak preference for NO versus IO (at 2.2σ), for CP violation versus conservation in NO (1.3σ) and for the first θ₂₃ octant versus the second in NO (1.1σ). We discuss the status and qualitative prospects of the mass ordering hint in the plane (δ m²,\,Δ m²ₑₑ), where Δ m²ₑₑ=|Δ m²|+1/2α(cos²θ₁₂-sin²θ₁₂)δ m², to be measured by the JUNO experiment with subpercent precision. We also discuss upper bounds on nonoscillation observables. We report m_β<0.50~eV and mββ<0.086~eV (2σ). Concerning the sum of neutrino masses Σ, we discuss representative combinations of data, with or without augmenting the ΛCDM model with extra parameters accounting for possible systematics or new physics. The resulting 2σ upper limits are roughly spread around the bound Σ < 0.2~eV within a factor of three. [Abridged]