Each Euro coin has a common side and a national side. Courtesy - Wikipedia

Each Euro coin has a common side and a national side. Courtesy – Wikipedia

As usual this is a quick guide, so I hope you easily find what you are looking for.

Currency symbols (€, £, $ etc) should be placed before the number, with no space, like this:
He earned €30,000 last year (spoken – thirty-thousand euros).
You can get a fast food meal for as little as $5 or $5.00 (spoken – five dollars) – if there are no cents then the zeros are unnecessary, but can be added for emphasis.
The software upgrade costs £99.99 (spoken – ninety-nine pounds ninety-nine pence).
Finland’s GDP in 2012 was $198.1 billion (spoken – one hundred and ninety-eight point one billion dollars).

Currency abbreviations, used in a formal report or newspaper writing,  (EUR, GBP, USD etc) should be placed before the number, with a space, like this:
The turnover of the company last year was EUR 354,345 (spoken – three-hundred and fifty-four thousand, three-hundred and forty-five euros).
In the year 2000, the people of the US spent USD 110 billion on fast food (spoken – a hundred and ten billion dollars).
The company turnover in 2012 was MEUR 15 (spoken – fifteen million euros).

Thousands should be separated by commas, like this:
Henry just won €5,540,280 on the lottery (spoken – five million, five-hundred and forty thousand, two-hundred and eighty euros) . 
The average gross monthly salary in Finland is €2,901 (spoken – two-thousand, nine-hundred and one euros).

Decimals (cents, pennies etc) should be separated by a dot/point/full-stop (whatever you want to call it), like this:
The book cost €12.99 (spoken – twelve euros, ninety nine cents – or just – twelve ninety-nine).
NOTE: If you are not talking about money then say – twelve point nine nine.

Percentages:
The percentage symbol follows directly behind the number, with no space, like this:
Corporate tax in Finland has just been reduced to 20%.

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