In the realm of financial transactions, milestone and installment payments are integral to fostering successful collaborations and empowering businesses and customers alike. Milestone payments ensure accountability, progress tracking, and confidence in project-based ventures, while installment payments provide financial flexibility and accessibility, making significant purchases more manageable for customers.

Milestone payments are a structured payment method used in projects or contracts where payments are released upon reaching specific milestones or achieving predefined project deliverables. These milestones are critical stages or objectives in the project's timeline. Milestone payments provide an effective way to ensure that work progresses as expected and that clients only release funds when they are satisfied with the completed work or a specific project phase.

For instance, in a software development project, milestone payments may be tied to the successful completion of the project's design phase, development phase, and final product delivery. Each milestone reached triggers a corresponding payment from the client to the service provider.

Installment payments, on the other hand, refer to dividing the total cost of a product or service into smaller, regular payments spread over a defined period. These payments are typically equal or relatively equal in value and paid at predetermined intervals (e.g., monthly or quarterly). Installment payments offer customers financial flexibility, allowing them to afford high-value purchases without paying the full amount upfront.

For instance, when buying buying a production machine, customers may opt for an installment plan, where they pay a portion of the total cost each month until the product is fully paid off.

Step 1 - Turn on the premium feature 'Custom fields as due date'

Settings >> Back Office >> Premium Features

Step 2 - Set the Number of Installments / Milestones as Date Custom Fields at the Invoice Level

For example:
The company is a Software Development Company. Each developments is like a project and the customer pay per successful completion of the following Milestones:

Milestone 1 - Project's design

Milestone 2 - Development

Milestone 3 - Final product delivery

In this case, the company needs to create 3 Invoice's custom fields.

Step 3 - Create a due date workflow rule for each of the milestones

Once you define that workflow email that will be sent X days before/ on / after the due date, the workflow mechanism will use the date defined in the selected custom field as a due date and will ignore the due date of the invoice itself