If PCN remains unpaid or is ignored, the authority that issued it has the right to increase the charge and register the outstanding amount as a debt.

28 days after either:
• receiving a Notice to Owner (parking PCNs only) or a PCN by post and either not paying the PCN or making representations to the authority;
• receiving a Notice of Rejection of Representations (after making representations to the authority that issued the PCN) and either not paying the PCN or appealing to an independent adjudicator;
• an adjudicator dismissing your appeal and not paying the PCN

you are likely to receive a Charge Certificate, which increases the penalty charge owed by 50% and means you no longer have a right to make representations (some authorities may still accept representations, but this will be at their discretion).

If the PCN remains unpaid 14 days after receipt of a Charge Certificate, the authority can register the debt with the Traffic Enforcement Centre at the Northampton County Court and you will be sent an Order for Recovery, with the risk of Bailiffs (‘civil enforcement agents’) taking action to collect the debt after 21 days.