Bad Debt is a debt which is not collectible and is worthless to the Creditor. As soon as the debt is bad, the business should be allowed to write off as an expense in its income tax return. The eligibility of the deduction is on the existence of debts which is irrecoverable is totally under the law.
Knowing how to invoice your customers properly is a key skill for entrepreneurs and business owners. Not just it ensures that you are paid for the goods or products, it also helps in preventing costly mistakes with respect to taxes and also keeps your books of account in order. Read here for more.