AIG United Guaranty (a marketing term for United Guaranty Residential Insurance Company) has insured residential mortgages for more than 45 years. Credit unions choose AIG United Guaranty because of its commitment to providing innovative programs and outstanding customer service. Our services include delegated underwriting authority, paperless origination and servicing via Web-based functions, a simplified claims process, and a comprehensive claims program. AIG United Guaranty. One Partner, Countless AdvantagesÂ®. Please see our website at www.ugcorp.com for a complete listing of our sales representatives.