Fishing fleets face fewer days at sea but bigger catch quotas after marathon talks which ended at dawn in Brussels.
UK Fisheries Minister Richard Benyon said he had secured "the best possible deal" for the fishing industry after three weeks of behind the scenes negotiations and two days around the negotiating table.
Britain fended off moves to cut fishermen's days at sea to just four a fortnight next year, in exchange for greater national fish conservation efforts.
But boats will still be confined to ports for longer than before - making it tougher to capitalise on some big rises in fish catch quotas which reflect that conservation is working in some regions.
Mr Benyon said: "After two days of tense and frustrating negotiations I am delighted to have secured the best deal possible for the UK fishing industry and ensure the future sustainability of our fish stocks.
"By arguing that we should follow scientific advice we have been able to agree quotas that will not only allow local fishermen to make a living but will also ensure that we can protect the environment."
His Scottish Government counterpart Richard Lochhead, said: "These have been the toughest of negotiations that have delivered both significant gains but also huge frustrations.
"Scotland's fishing industry has endured three weeks of anxiety following Europe's initial decision to cut the fleet's time at sea and prevent it from catching our quotas. Now that particular threat has been lifted as a result of talks in Brussels and our fishing communities can breathe a sigh of relief."
Major increases in catch allowances for 2012 include a doubling of the north-east coast herring quota and a 150% rise in south-west cod catches. Smaller rises include 25% bigger catches for south-west haddock, and 15% increases each for north -east haddock and north-east and south-west whiting, and a 9% rise in Channel sole catches.
The retention of this year's Northern Irish scampi catch allowance will help protect the region's fishing industry in 2012, said Mr Benyon.