Methodology
How PenCompare Calculates and Ranks Provider Costs
Every price and every ranking position on this site is produced by a documented, repeatable rule — never by editorial preference and never by what a provider pays us. We publish those rules in full, in plain language, so you can check our working before you rely on a number.
The six pillars behind every figure
Each pillar is documented separately and versioned, so changes to our approach are visible rather than silent.
Comparison methodology
What we include, what we exclude, and the total-cost basis we use so two providers with very different fee structures can be read side by side.
Ranking
Results are ordered organically by lowest total cost. Affiliate commission never influences position. Any sponsored placement is visually isolated and labelled as such.
Data freshness
How often each price is re-checked, how we timestamp it, and what we display when a provider’s published price cannot be verified.
Provider verification
Every listed pharmacy is checked against the GPhC register, or the PSNI register in Northern Ireland, before it appears — and re-checked on a fixed cycle afterwards.
Price corrections
How to report a price you believe is wrong, the window we work to when correcting it, and how each correction is recorded.
Funding and affiliates
How PenCompare is funded, which links earn us commission, and the separation we hold between commercial revenue and comparison output.
Important
This is cost information, not medical advice
PenCompare compares the published prices and service terms of registered providers. We do not provide medical advice, diagnosis, or treatment recommendations, and nothing on this site should be used to decide whether a particular medicine or treatment is appropriate for you. Always speak to a GP, pharmacist, or another qualified healthcare professional before starting, changing, or stopping any treatment.