If me and my wife are the only members in our multi-member LLC can we file it as a disregarded entity? Do we have to file as a partnership?

It depends on what state you live in.

If you do not live in a community property state, the multi-member LLC has to be treated as a partnership. The LLC has to file a partnership tax return, Form 1065, separate from your personal Form 1040 tax return.

If you and your wife are the only members of the LLC, and you live in a community property state, you can choose to treat the LLC as either a disregarded entity or a partnership. To treat it as a disregarded entity, you must both hold your interests in the LLC as community property. If you choose to treat it as a disregarded entity you and your wife would each file a Schedule C for your respective shares of the business income and expenses.

The community property states are Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin.