At one loop, we provide an explicit formula for the ground state of the one- soliton sector in the sine-Gordon theory. The state is given in the basis of eigenstates of the field operator, or equivalently as a Schrodinger wave functional. The formula readily generalizes to other solitons in other models and as an example we also provide the ground state of the kink in the (1+1)-dimensional ϕ4 double well.