Postal voting intends to provide citizens residing abroad with a convenient voting technique to influence political representation in their country of origin. However, its adoption among individuals is dependent on two opposing factors. On the one hand, voting via post helps to overcome the increasing distance between a voter’s residency abroad and the nearest polling station organized by a diplomatic mission (mostly at an embassy or a consulate). On the other hand, this way of voting also requires enough trust that the postal service and designated state office will successfully deliver one’s vote to the ballot box because the result cannot be effectively verified without violation of the ballot secrecy. We examine the interaction of these two factors in an originally conducted survey among Finnish citizens residing abroad fielded shortly after the 2019 Parliamentary elections—the first occasion after Finland put postal voting into effect. Altogether, 664 respondents responded to all questions required for our specification of binomial logistic regression models controlling for various potential confounders. The results demonstrate that trust in postal voting moderates the impact of distance on one’s probability to adopt postal voting. While low-trusting emigrant voters remain largely indifferent regardless of the distance to the nearest polling station, medium-trusting non-resident citizens increasingly mail their ballots when the nearest polling station is more than 100 km away. High-trusting individuals begin to increasingly do so when they are ten to 30 km away.