They say absence makes the heart grow fonder. That may be particularly true in the workplace. If you're looking for a raise, passing on your accrued time off won't help your case. Let them get by without you for a while. If you're truly deserving of the bump in pay, your point will make itself. A recent survey, published by PR Newswire indicates people who take at least 11 vacation days a year greatly enhance their chance of getting a pay increase. The survey also says the #1 reason people don't take time off is their concern about returning to  a mountain of work. Americans took about 20% more time off between 1976 & 2000 than we do now. We reportedly squandered a record number (658 million) of vacation days last year. If that doesn't convince you, consider this. Not using paid time off is essentially the same as leaving money on the table.