With  the  emergence  of  new  technologies,  user  transactions  have  become  increasingly digital  and  thus  anonymous.  As  a  result,  online  platforms  started  offering  new  user identity  verification  mechanisms  including  online  verification.  However,  convincing users to verify online represents a challenge as benefits must be carefully balanced with resulting risks. We combine Toulmin’s model of argumentation with Regulatory Focus Theory to develop communication arguments to nudge users into online verification. Two argument  types  consisting  of  both  claim  and  claim-supporting  data  are  employed:  a promotion-focus  argument  conveying  convenience  and  a  prevention-focus  argument aiming to reduce privacy concerns. In a controlled experiment, we find that both claims significantly increase online verification conversion rate if supported by data. The effect of a prevention-focus claim is stronger than that of a promotion-focus claim. However, if a  prevention-focus  claim  is  not  supported  by  data,  it  actually  decreases  online verification rate compared to if no claim is shown.