Methods and systems are disclosed for processing a request to fund a purchase from a provider with a medical expense account. The request identifies expenses incurred with the purchase is received at a substantiation system and used to identify the provider. A determination is made whether the provider is included in a presubstantiation list, which identifies a set of providers determined to provide only goods and/or services eligible for funding by medical expense accounts. In response to a determination that the provider is included in the presubstantiation list, the expenses are automatically substantiated and substantiation information is generated and transmitted to a third-party administrator.