KEY POINTS
  • April 15 is the federal tax deadline for most filers and could be the last chance to avoid a penalty.
  • There's still time to file an extension, which pushes the filing deadline to Oct. 15. But you still must pay taxes owed by the due date.
  • Many taxpayers can still file for free with IRS Free File or Direct File.

The federal tax deadline is here — and experts have tips as the IRS braces for a flood of last-minute returns.

"On a day like today, April 15, we might see a million returns come in every hour," IRS Commissioner Danny Werfel said Monday on CNBC's "Squawk Box."