The 24-year-old Irishman, who moved to Welford Road from Leinster in 2011, has scored seven tries in 26 appearances for Leicester, including two in last Saturday's league victory at London Irish.
Leicester director of rugby Richard Cockerill said of the wing/full-back: "Niall made a big decision to leave Ireland and come to Leicester last summer and he has been been a very important member of the squad here for the last two seasons.
"He has been improving the whole time with us. He is a good young player who is developing really well and doing a good job for us."
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
$29.99
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.
