U-Pb dating of carbonates by LA-ICPMS spot analysis is an increasingly used method in the field of geosciences, as it brings very strong constraints over the geological history of basins, faults or reservoirs. Most ages currently published are based on the measurement of U and Pb ratios on spot ablations, using nanosecond lasers coupled to sector-field or multi-collector ICPMS. Here, we present a new strategy for the U-Pb dating of carbonates from 2D isotopic ratio maps, based on the 15 use of a robust regression approach in the data reduction workflow. The isotopic maps, having minimum area of 0.65 mm 2 (∼1000 pixels of 13x25 µm resolution), are obtained using a 257 nm femtosecond laser ablation system at high repetition rate (500 Hz) coupled to a High Resolution ICPMS. The maps commonly show significant variations in isotope ratios at the pixel scale, allowing the plotting of pixel U-Pb ratios in concordia or isochron diagrams and the calculation of U-Pb ages. Due to the absence of individual ratio uncertainties, the ages are calculated by using MM-robust linear regression rather than the more 20 commonly used York-type regression. Provided examples demonstrate that this strategy allows calculating ages and uncertainties similar to those obtained for samples already dated by more traditional techniques (isotope dilution or LA-ICPMS spot analyses). The goodness-of-fit to the data is assessed by the calculation of the residual standard error of the regression (RSE), and by the calculation of a MSWD on discretized data. The regression method proposed is a statistically robust, alternative approach to that proposed by Drost et al. (2018), that can be easily applied to U-Pb age determination from isotopic 25 maps.