Just because you're enjoying a portion of the trip, doesn't mean it's not a write-off in the eyes of the government. The number one rule to remember is to document everything.
"The tax law specifically requires you to do certain record keeping for travel and entertainment costs," said Barbara Weltman, author of 1001 Deductions & Tax Breaks. "The government is not stupid and they know that this is an area where there is potential for abuse because the line between personal and business is often grey."
Nowadays, smartphones and tablets make tracking expenses a breeze with free travel recordkeeping apps like Expensify and Concur. These apps let you take pictures of your receipts, which the software then scans for the necessary information. They also let you upload credit card transactions, email receipts, and a variety of other time-saving tasks.
When it comes to writing-off airfare, Weltman says you can deduct 100 percent of it, if the primary purpose for the trip is business, even if other pleasure related activities will take place.
"It's no coincidence that many of the conventions are scheduled in Las Vegas, New Orleans, Orlando—because there's the opportunity for people to unwind and relax and have some fun," said Weltman. "There's no bright line here, there's no number of days that you have to spend on business, but as long as you can say, 'you know, I wouldn't have taken the trip but for the business,' as long as it's the primary purpose, then you can deduct all of your airfare there."
Lodging however is a different story, with deductions only applied to the days when business was conducted.
But, according to Weltman, it all comes back to recordkeeping. Being smart about it now will save you money down the road in legal fees and tax penalties.