I’ve been branded a liberal feminist, a neanderthal conservative, and everything in between. But from my perspective, I just aim to line up everything I do or think with the Word of God. Sometimes that makes me “liberal” by today’s standards. Sometimes it makes me “pro-women’s rights.” And other times it makes me, well, old school. Call it what you will–

Any case, here’s my liberally feminist neanderthally conservative Christian view of whether women should change their last names when they get married.

First, let’s acknowledge that changing your last name is hard. Really hard. It’s wise to recognize that there will be a grieving process involved if you change your name. Whenever we lose something, it triggers grief responses in us — even if we’re gaining something better in the process (e.g., grieving after the birth of your first child because you’ve “lost” the freedom that comes with not having children). Recognizing that grief reaction and allowing yourself to work through it is really healthy.

There are a lot of practical considerations involved in changing your name, but I think they are far outweighed by the principled decisions. In our culture, women’s last names denote which family/man they’re associated with. For example, as a Lee, you are associated with/cared for by a Lee man (in this case, usually the woman’s father). But when you become a Smith, you are associated with/cared for by a Smith man (your spouse).
It’s a hard thing to leave one family and join another — to leave your childhood family and start a new family with your spouse. And that’s ok. It might help to realize you already made this choice when you chose to get married. Changing your name simply reiterates the choice you already made.
And I think that’s biblical (not the name change so much, but the declaration of your allegiance). Like Ruth, be sold out in your marriage. Pick your husband over everyone else — dad, mom, brother, sister, even your kids. Your relationship with him is the only covenant relationship you have in this world. So changing your name to show your oneness with him is a huge statement of principle, and it’s wise.
I say share names, bank accounts, vacations, a bed, etc. — as much as you can, really. The more you’re unified in the practical things, the more you’ll be unified in heart and spirit.