Ammonia (NH3) is considered a promising carbon-neutral fuel, with a high hydrogen content, that can diversify the global energy system. Blending ammonia with a highly reactive fuel is one possible strategy to enhance its combustion characteristics. Here, an investigation of blends of NH3 and dimethoxymethane (DMM), a biofuel with high fuel-born oxygen content and no carbon-carbon bonds, is reported. Unstretched laminar burning velocity (S-L) and Markstein length of different NH3/DMM blends were experimentally determined using spherically propagating premixed flames. The DMM mole fraction was varied from 0.2 to 0.6 while measuring S-L at 298 K, 0.1 MPa, and equivalence ratios (Phi) over the range of 0.8-1.3. The addition of DMM was found to immensely enhance the combustion characteristics of ammonia. DMM 20% (by mole fraction) in the NH3/DMM blend increased S-L by more than a factor of 3 over neat ammonia; such enhancement was found to be comparable to 60% CH4 in NH3 (Phi = 0.91.1) blends. Increasing Phi was found to significantly decrease the burned gas Markstein length for lean cases, whereas a negligible effect was observed for rich mixtures. A composite chemical kinetic model of DMM/NH3, aimed at interpreting the high-temperature combustion chemistry, was able to reliably predict S-L for neat NH3 and DMM flames. Also, the predictive capability of the kinetic model to describe S-L for DMM/NH3 blends is reasonably good. Sensitivity analysis and reaction path analysis indicated that the NH3/DMM blends could be understood as dual oxidation processes of the individual fuels that are competing for the same radical pool.