Auditing a school district in Cincinnati served by Duke Energy for electric and Duke Energy Ohio for gas. The electric accounts have the government sales tax exemption properly applied — no tax on those bills. But the natural gas accounts are paying full Ohio sales tax. Same school district, same exemption status, different utility division. Looks like the exemption certificate was only filed with the electric division and nobody filed it with the gas side.
School district paying sales tax on natural gas — exemption applies to all utilities
Happens all the time when the electric and gas are technically separate entities or separate billing systems even under the same parent company. AEP Ohio electric and Columbia Gas of Ohio are completely separate companies — an exemption filed with one does nothing for the other. Even within Duke Energy, the electric and gas billing systems may not share exemption status. Always check every utility account individually to verify the exemption is on file. Don't assume that because one account is exempt, all accounts are.
Carla identified a textbook example of a partial exemption filing — the customer filed with one utility but not another. Eugene is exactly right that exemption certificates are account-specific and utility-specific. For any client with multiple utility providers or multiple commodity types (electric, gas, water), verify the exemption status on every single account. This is particularly common with government entities and nonprofits that have multiple facilities across different utility territories.
Filed the exemption certificate with Duke Energy Ohio gas division. They processed a 3-year refund of $18,500 in sales tax on the gas accounts. The electric side was already exempt so total value of the gas finding alone paid for the entire audit engagement. Now I check gas, electric, water, and telecom separately for every exempt client.