Getting your Pokemon cards graded can take a while, and it can cost you about $25 per card. With that in mind, you should consider getting your card graded so long as its value exceeds about $25.
Some exceptions apply. For example, if you own an entire base set that you’re looking to sell (or display), getting each card graded may be worth it — even if an individual card is worth less than $20 — as having the entire set graded would enhance its overall value.