We prove that Allard’s regularity theorem Allard (Ann Math 2(95):417–491, 1972) holds for rectifiable n-dimensional varifolds V assuming a weaker condition on the first variation. In particular, we do not assume the first variation to be bounded. Furthermore, we obtain a boundary regularity theorem in this setting thereby generalizing Allard’s boundary regularity theorem Allard (Ann Math 101(2):418–446, 1975) [cf. also (Bourni in Adv Calc Var 9(2):143–161, 2016)].