Time preferences may explain public opinion about a wide range of long-term policy problems with costs and benefits realized in the distant future. However, mass publics may discount these costs and benefits because they are later or because they are more uncertain. Standard methods to elicit individual-level time preferences tend to conflate risk and time attitudes and are susceptible to social desirability bias. A potential solution relies on a costly lab-experimental method, convex time budgets (CTB). We present and experimentally validate an affordable version of this approach for implementation in mass surveys. We find that the theoretically preferred CTB patience measure predicts attitudes toward a local, delayed investment problem but fails to predict support for more complex, future-oriented policies.