In most cases, businesses award bonuses based on performance. Whether you're writing a justification letter for yourself or penning one for an employee, you'll be most successful if you focus on quantifiable results, rather than personal qualities such as loyalty or a good attitude. Present your information clearly and professionally, and make every effort to tie the results to your company's requirements for bonuses.

Review the Requirements

Most companies outline their requirements for awarding bonuses. A performance-based bonus, for example, might be based on a specific number of sales, a response time for customer service specialists, or a quantity of items produced or services rendered. A hiring bonus may depend on level of education or experience. Research your company's bonus requirements carefully before you make a request, and consult human resources if you have questions.

Assemble Your Data

Use the bonus requirements to determine what type of information you should include in your justification letter. Whenever possible, include quantifiable, verifiable data, such as sales results from a quarterly report or scores from customer satisfaction feedback forms. Augment the hard data with other relevant information, such as positive client feedback or excerpts from an annual performance review.

Write Your Justification

Some companies use forms for bonus justifications. If yours is one of them, fill it out completely and correctly. Otherwise, write a justification letter formally addressed to the appropriate party -- most likely your supervisor or an executive in human resources. Follow the principles of professional business communication and create a narrative that demonstrates how you have met the bonus requirements. If you have the option, attach backup documentation, such as reports and reviews.