When does it make sense to file jointly versus separately? I am married and my wife makes approximately the same amount of money as me.

In almost all cases from a tax standpoint it is better to file as Married Filing Jointly versus Married Filing Separately.  When filing jointly you receive the highest Standard Deduction of $24,400 if under age 65.  You are eligible for more tax credits and/or increased deductions when filing MFJ versus MFS.  Your tax brackets are lower when filing jointly.

See this TurboTax support FAQ for filing jointly versus separately - https://ttlc.intuit.com/community/married/help/is-it-better-for-a-married-couple-to-file-jointly-or-separately/01/25590