0800 numbers are considered "freephone numbers" and come with no cost for customers to call from both landlines and mobiles, making them an excellent option for businesses looking to boost customer engagement and satisfaction. You would typically choose this number for any customer service or sales enquiries as it is a cost-free method for your customers to reach you.
On the other hand, 0300 numbers are "non-geographic numbers" and cost the same to call as a standard landline number, even from a mobile phone. These numbers are a good fit for organisations wanting a national presence without being tied to a specific location, including not-for-profits, charities, and some businesses. While not free, calls to 0300 numbers are often included in callers' free minutes, making them a cost-effective choice for your business and your customers.