There are 11 elements of an estimate that you should be aware of, some of which are necessary while others can be used for customization.

1. Title: In order to avoid confusion, it's important that your estimate is titled properly and clearly states "estimate". This helps prevent getting invoices mixed up with estimates, and the document isn't legally binding without a proper title.
2. Description: A description helps your customer understand the nature of the goods and services that the estimate is for.
3. Your Company's Name & Address: The name and address of your company is usually displayed at the top of an estimate in order to indicate the company that is providing the estimate for services rendered.
4. You Customer's Name & Address: It's also important to indicate who is receiving the estimate. Entering your customer's information ensures you'll send the estimate to the right person, and it helps to avoid misplacing or mixing up estimates.
5. Estimate Number: Every invoice has a unique identifier in the form of an invoice number, which helps you keep track of multiple invoices. Invoice numbers can be formatted in different ways such as file numbers, billing codes or date-based purchase order numbers.
6. Estimate Date: The receipt date indicates when payment for goods and services was received. This helps you keep track of when you've received payment for goods or services you've provided to customers.
7. Valid Until Date: Businesses providing an estimate for services generally state a time to sign the contract. The "valid until" date is the date until which the estimate is valid and is the last date for signing the contract at the quoted cost.
8. Line Item: Each line item on an invoice should have a name for the goods or services provided, along with a description of those goods and services. The line items also require a quantity so the customer knows how many goods or services they are being billed for, the price of the line item and tax rate applied to it, and the amount the line item costs.
9. Tax: Indicating the tax rate applied to the cost of the goods or services provided is legally required on estimates. This rate may differ depending on the geographic location you're business operates in. So please consult your local tax resource to determine how much tax you should be applying to your estimates.
10. Notes: Within the notes section of the estimate, you can stipulate any additional terms of service that you've agreed to with your customer.
11. Total: The total displays the balance due which is calculated from the amount of each line item on the invoice. This is what your customer is required to pay you.