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Fast Radio Bursts have recently been used to place limits on Einstein'sEquivalence Principle via observations of time delays between photons ofdifferent radio frequencies by \citet{wei15}. These limits on differentialpost-Newtonian parameters ($\Delta \gamma<2.52\times10^{-8}$) are the best yetachieved but still rely on uncertain assumptions, namely the relativecontributions of dispersion and gravitational delays to the observed timedelays and the distances to FRBs. Also very recently, the first FRB host galaxyhas likely been identified, providing the first redshift-based distanceestimate to FRB 150418 \citep{kea16}. Moreover, consistency between the\omegaigm\ estimate from FRB 150418 and \omegaigm~expected from $\Lambda$CDMmodels and WMAP observations leads one to conclude that the observed time delayfor FRB 150418 is highly dominated by dispersion, with any gravitational delayssmall contributors. This points to even tighter limits on $\Delta \gamma$. Inthis paper, the technique of \citet{wei15} is applied to FRB 150418 to producea limit of $\Delta \gamma < 1 - 2\times10^{-9}$, approximately an order ofmagnitude better than previous limits and in line with expectations by\citet{wei15} for what could be achieved if the dispersive delay is separatedfrom other effects. Future substantial improvements in such limits will dependon accurately determining the contribution of individual ionized components tothe total observed time delays for FRBs.

Limits on Einstein's Equivalence Principle from the first localized Fast Radio Burst FRB 150418