How can I increase the number of seats on my licence?

If you wish to add additional licenses to a single product on your account, you can increase the quantity in your MyMaxon account and pay the difference, keeping a single subscription and renewal date. 

Go to Subscriptions along the top.

Click the "Upgrade now" button for the product you wish to purchase more seats for.

Then, for the current product, increase the Quantity value to the number of seats you wish to own.  
You can enter a maximum of 20 per subscription. If you need more than 20 licences, you would need to start a new subscription but this cannot be paid pro-rated.

The "Total price" will update to reflect the amount you will be paying today when you upgrade.

Finally, click the Upgrade Now button in that same product box and complete the checkout process.

Note - this will increase the number of licenses for a single product on 1 account. These cannot be allocated to different accounts or accessed by multiple users. It can only be managed and activated by the original account. To be able to allocate the seats to multiple user account, you will need to upgrade to Teams licensing instead, which can be done from this same screen.