I live in delaware and work in Maryland can I use just one turbo tax or do I need to purchase two?

[ChrisJ]

TurboTax Online will allow you e-file up to 5 state returns and one federal return. No state returns are included with Online software - one state return is included with CD/Download purchases. To compare other product features and benefits, visit here. 

Some states have reciprocal agreements, allowing residents of one state to request an exemption from tax withholding in the other (reciprocal) state. Click here for more information, or here to see which states have reciprocal agreements.

 If you're trying to add another state return online, please refer to these steps:

1. Sign in and open your return (can't? Go here)
2. Click on the State Taxes tab across the top. 
3. Select Add Another State beneath where selected states are displayed (refer to attached image)