Studies of lesbian, gay, bisexual, and transgender (LGBT) people suggest that they are more politically engaged and active compared to cisgender and heterosexual people. However, knowing the voter registration rates of eligible LGBT Americans has been elusive because the U.S. Census Bureau does not document sexual orientation or gender identity in the Current Population Survey and existing estimates are limited based on small sample sizes or on self-reports, which have social desirability biases. The 2016 and 2018 Cooperative Congressional Election Survey merges respondents to their official voter status as contained in state voter files, which overcomes biases in self-reported registration status. We provide demographics and estimates of voter registration rates by sexual orientation and gender expression. Many gaps in registration rates are attributable to demographic differences between groups, though lesbians and gay men were registered at greater rates than heterosexuals even after adjusting for demographics. Transgender Americans were the least likely to be registered to vote, though this may be due to the vote-validation process itself.