Lifeboat crews in the North rescued more than 3,000 people in 2015.
During the Cumbria floods alone in early December, the RNLI helped 400 people in Kendal, Cockermouth and Carlisle.
The charity says Fleetwood and Blackpool were the busiest stations last year.
Andrew Ashton, RNLI Divisional Operations Manager in the north of England, said: "The RNLI’s volunteer lifeboat crews and lifeguards have once again had a busy year and I want to thank them for their hard work and dedication to saving lives. However, they couldn’t carry out their crucial role without the army of fundraisers and other volunteers who raise money and awareness of the RNLI in their local communities – they are the lifeblood of our charity.
"Many of our volunteers joined colleagues from other charities and emergency services to help during the terrible floods at the end of 2015, rescuing 400 people in Cumbria. It was dreadful to see the devastation caused by the floods, which at their worst can be very dangerous. We would remind anyone in a flood situation to be aware of fast flowing flood waters and to always keep a safe distance."
Mr Ashton added: "Our 2015 rescue statistics emphasise the need for everyone to respect the water and follow simple safety advice before heading to the coast. Some very basic precautions can keep people safe on and by the sea which, by its very nature, is unpredictable and can catch out even experienced water users.
"Checking a vessel’s engine and fuel before setting out to sea should help prevent our most common cause of rescue, machinery failure. Finding out tide times before going for a walk along the coast can make the difference between a pleasant day out and getting cut off by the tide. Always avoid places where you could be swept off your feet during stormy weather and, if you are visiting the beach in the summer and want to swim, be sure to visit a lifeguarded beach."