Asking your girlfriend to move in is a serious commitment to a long-term relationship. Living together implies not only that you want to spend your time with one another, but that you are ready to take on the emotional, personal and financial challenges of life with one another. Although many couples believe in the concept of cohabitation prior to marriage, you may want to have some serious conversations with your girlfriend before asking her to move in.
Define your current relationship with your girlfriend. Is your girlfriend someone with whom you could spend almost every waking moment? Can you envision being with her in one year, or five or ten? Is she financially trustworthy? If so, moving in with your girlfriend may be a step in the right direction for you.
Ask your girlfriend about her candid opinion on moving in together. Although some people and families share a liberal view of cohabitation before marriage, others do not. It may be hard to convince your girlfriend to move in with you.
Tell your girlfriend how you feel about her and about your relationship together, and then express your interest in moving in with her. Let her know that you believe that moving in together is the next step in your relationship.
Discuss the logistical aspects of moving in together, including finding an apartment or house that you can both afford, figuring out how to split the bills and handling questions about your living situation such as "When will you get married?"