It is amazing once you start to look at what the officials earn to see where they fit into the big picture. This is a crucial part of the game and they should be rewarded for doing a thank less job. Not many people are drawn to refereeing especially ex players which I think is a big mistake. This should be encouraged in my opinion and they should be rewarded accordingly.
The VAR system was used at the weekend in the English Premiership and according to 
Football is a huge sport with massive interest so you would think that they are the highest paid. This isn't always the case and there are some surprising sports that will raise a few eyebrows on this list. Some of the figures are slightly out I assume as I pulled whatever figures I could find and will bracket what year that information was correct.
Football
Semi professional £80 per game plus match expenses such as travel.
Top Flight retainer for the season is between £38,500 and £42,000 plus another £1150 per game which will see them earn around £70 000 per year. Not great in my opinion and a slap in the face for the officials. Players earn that in less than a week and they are meant to respect the officials.It also depends what country you are in on how much you earn as well.
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Don't ask me why the referees are paid differently in the various countries but the differences are huge and the English Premiership should be ashamed being bottom of the table.
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One sport that kinds of throws all the other sports out as the salary is whopping for what they do.
Snooker $500 per match $250 000 per year (2017)
Rookie ref in snooker $90 per match and $50 000 per year.
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Tennis
A top tennis umpire(Gold badge) will expect to receive £50-£60,000 per annum but it takes many years to get to this point. A line judge can expect to receive £20 000 per annum.
Rugby
Young up and coming referee around $500 per match and a professional at $1500 per match. Top flight referees make in the region of $220 000 per year. Tournaments such as the World Cup are extra and a referee on the panel would expect a bonus of another $50 000. When I started I was on around $100 per match and that was not the top flight either.It takes a good 5 years to make that and it is seriously a good career. Flying around the world with all expenses paid.
NHL (Ice Hockey)
An average salary of a referee in the national hockey league is between $165 and $400 000 as it depends on the number of games officiated over the season. A linesman is receiving $110 000 to $235 000 also on how many games.(2018)
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Basketball (NBA)
A junior referee will earn somewhere in the region of $150 000 per year while a more established senior referee will earn upwards of $500 000. Not bad for officiating a sport you enjoy.
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American Football (NFL)
This has increased slightly over the years bringing them into line with other American sports. An average salary by a ref in this field will expect somewhere around $210 000 per annum.
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Baseball
Major League umpires start at $120 000 and rise to $350 000 for the season. It all depends on experience and time doing the job.
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Cricket Umpires
They receive an annual salary of $35000 - $45000 per year plus on top of that will receive match fees. $3000 for a test match plus $2200 for a one day match. This is for the elite panel of 10 though and will drop considerably for First Class cricket. An India Premier League umpire will expect around $2800 per match and there are literally plenty of matches over the tournament. A top umpire doing tests and one day games plus the IPL would receive in the region of $150 000 per year and maybe more.
This just highlights how badly paid the English premiership referees are paid and Snooker of all things is deemed a better paid job. Now with VAR coming in to the game they are going to be under the spot light even more and who would do that for such a paltry figure. I know most of you are saying that £70 000 isn't pocket change,but hardly what they should be earning for the flak they take week in and week out. maybe if they paid more they would get a higher caliber of person officiating their games.