Everton
The Internazionale are the only team in Serie A to never be relegated to Serie B.
No, Real Madrid have never been relegated from La Liga. In fact Real Madrid C.F. , F.C. Barcelona and Athletic Bilbao are the only teams that have never been relegated.
I believe you're talking about being relegated to Serie B, the second division, as Serie A is the main league, comparable to the Premiersihp or the Bundesliga. Said that, Internazionale Milano (commonly known as Inter) is the only team to have never been relegated from the Serie A to Serie B.
liverpool
Arsenal is the only club in the E.P.L.ho have never been relegated, so they have the longest reign in England.
It is Real Madrid and Barcelona
Christiano Ronaldo joined Manchester United from Sporting Lisbon , and as Manchester have never been relegated for many years so neither has Ronaldo been relegated.
wigan
Leicester City lost 0-1 to Manchester City in the 1969 FA Cup Final and were relegated, as they finished 21st in the 22-team First Division. More recently, Middlesbrough lost 0-2 to Chelsea in the 1997 FA Cup Final and were relegated as they finished 19th in the 20-team Premier League. http://www.myfootballfacts.com/FA-CUP-FINALS-1871-72-to-2008-09.html
There are no league teams still in existence that have never been relegated. Arsenal are the team to have gone the longest without relegation. Quite right. Arsenal were only relegated once in their entire history - in 1913. They were voted back into the top division in 1919 and have remained there ever since, longer than anyone else.
Amazingly, Arsenal is the only major team in the world to not get relegated in any forms. This fact is not known by many and people will thought that Manchester United has not been relegated before. However, Manchester has been relegated in the 75/76 season!
Notts County are the team that throughout there history have taken the record of most relegated and promoted team in the world