You can still file your tax return at any time after the deadline. The only downside is you might miss out on tax credits and benefits, and you may face interest charges and other penalties. That’s why it’s recommended that you file your tax return as soon as you can. Those with extenuating circumstances can request an extension, which can push your deadline a bit further away. However, even with an extension, you will still need to pay any tax owed by the original deadline to avoid any extra charges.