Contract Glossary
Addendum
Definition
An addendum is a new document you tack onto an existing contract to add terms that weren't in the original. Both parties sign it, and it becomes part of the deal — no need to rewrite the whole contract.
In Practice
Say you signed a 6-month consulting agreement, and now the client wants you to handle their social media too. Instead of drafting a new contract, you write an addendum that adds the social media scope and adjusts the fee from $3,000/month to $4,500/month. The original contract stays intact — the addendum just bolts on the new stuff.
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Frequently asked questions about addendum
An addendum adds new terms. An amendment changes existing ones. If you're adding a new service to your contract, that's an addendum. If you're changing the payment deadline from Net 30 to Net 45, that's an amendment. Both need signatures from all parties.
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Create your contractThis content is for informational purposes only and does not constitute legal advice. For contracts with significant financial or legal implications, review by a qualified attorney is recommended.