what if too little is withheld 
the short answer you are likely to owe money at tax time and if you have significantly underpaid your taxes during the year you may have to pay a penalty when you file your annual tax return if you do not have enough withheld from your paycheck you can request that your employer withhold an additional dollar sum if on the other hand you have more income withheld than you should you will receive a refund after you file your annual income tax return receiving a refund isn t necessarily a good thing it represents money you could have used throughout the year to pay your bills or invest for your future financial well being 