Database Schema for SaaS Appliaction

Hi ,

I have a SaaS application and I want to be sure if my database schema is good and perfect. And it doesn't make me in a trouble in future. I have 3 models ( Plan, Company, CompanyPlan).

Plan: id , name , price_monthly , price_annuel

Company: id , name

CompanyPlan: id , company_id , plan_id ,start_date , end_date

So, I want to make good relationships between models, and make query if this company have a subscription or not.

Can you give me an advice for database schema and relationship?

thank you