How to use “as” in formal writing

This is how to use “as” in business emails and letters.

• As has a similar meaning to because.
• We use as to give the reason for a situation.
• As is more formal than because.

We can use as at the beginning of a sentence:

• As he is on holiday [reason], it is not possible to get his signature on the letter. [situation]
• As we do not have the goods on stock at the moment [reason], we are not able to send your order. [situation]

We can also begin with the situation, then use as in the second half of the sentence:

• It is not possible to get his signature [situation] as he is on holiday [reason].
• We are not able to send your order [situation] as we do not have the goods on stock at the moment. [reason]