Generic bank, insurance and other financial forms are inadvertently outing gay couples, according to new research.
A study from Citizens Advice reveals gay and lesbian couples are forced into revealing their sexual orientation in forms when required to state marital or partnership status.
Also many forms do not have the option to write civil partnership.
One interviewee said: "I'm no longer ticking single [on forms], but I can't tick married because I'm not married .but it's difficult because not all forms are up-to-date."
The Another Year On report - marking two years since civil partnerships were brought in - reveals a number of emotional, financial and social costs which have arisen as a result of the legislation.
Citizens Advice is now calling on financial firms to opt for a single status box on forms for married/civil partner, leaving the sexual orientation of applicants unspecified.
It added: "Perhaps more significantly, organisations should be challenged to consider whether they really need information regarding a person's marital or partnership status."
The report also found many people heading into a civil partnership do so out of both emotional and practical or financial reasons - but not all had factored in all the implications of their decision.
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