Due to a Washington, D.C., holiday and the weekend, the 2017 tax return filing deadline for individuals is Tuesday, April 18. The IRS will consider a paper return that’s due April 18 to be filed on time if it’s postmarked by midnight. However, dropping your tax return mailbox on the 18th may not be sufficient.
Example 
If you mail your return with a payment on April 18 but the envelope gets lost, you won’t find this out until a couple of months later when you notice that the check still hasn’t cleared.Then you refile and send a new check, but despite your efforts to timely file and pay, you’re hit with failure-to-file and failure-to-pay penalties of $1,500.Reducing Tax Return Penalties and Risk
To avoid this penalty risk, use certified or registered mail or a private delivery service designated by the IRS to comply with the timely filing rule, such as:

  • DHL Express: 9:00, Express: 10:30, Express: 12:00, or Express Envelope
  • FedEx First Overnight, Priority Overnight, Standard Overnight, or 2Day
  • UPS Next Day Air Early A.M., Next Day Air, Next Day Air Saver, 2nd Day Air A.M., or 2nd Day Air

Keep in mind that if you use an unauthorized delivery service, your return isn’t “filed” until the IRS receives it. See IRS.gov for a complete list of authorized services.

Another Way to Avoid Filing Late
If you’re worried about meeting the April 18 deadline, another option is to file for an extension.  But if you owe taxes, you’ll still need to pay by April 18 to avoid risk of late-payment penalties as well as interest.

If you’re owed a refund and file late, you won’t be charged a failure-to-file penalty. However, filing for an extension may be a good idea.

Contact your advisor to determine whether filing for an extension makes sense for you and help estimate whether you owe tax and how much you should pay by April 18.