The current charge for all NHS prescriptions from 1st April 2008 is:
Prescription: £7.20
12 month Prepayment Certificate (PPC): £102.50
3 month PPC: £27.85

Full details are contained in:

• HC12: Charges and opitical voucher values from 1st April 2008

You must pay this unless you fulfil one of the following criteria

 Revised October 1999

• A patient under 16
• A patient aged 16, 17 or 18 and in full time education
• A patient aged 60 or over
• A patient with a valid exemption certificate showing a medical exemption
• A patient with a valid exemption certificate showing that she is an expectant mother
• or has given birth within the last 12 months
• A patient with a valid exemption certificate showing evidence of being a war
  disablement pensioner; exemption applies only for drugs and appliances to treat the
  accepted disablement
• Has a valid pre-payment certificate
• Is named on a current HC2 charges certificate
• Was prescribed free of charge contraceptives
• Gets income-based Jobseeker’s allowance (JSA (IB))
• Gets Income Support (IS)
• Is entitled to, or named on, a valid NHS Tax credit exemption Certificate
• Has a partner who gets Pension Credit guarantee credit (PCGC)

For a more detailed look at these exemptions follow:

http://www.ppa.org.uk/ppa/hwhc.htm

If you are unable to obtain exemption because you fail the means test for acceptance, you may alternatively wish to purchase a pre-payment certificate. This works out cheaper if you have more than 5 items in 4 months or 14 items in 12 months. These are available in four and twelve-month durations and cost will £34.65 (4 month PPC) and £95.30 (12 month PPC) [from 1 April 2004]. These can be obtained online at the Prescription Pricing Authority or via their telephone advice and order line (0845 850 0030), from authorised chemists, or by post (form FP95 available on DH website).

More information on NHS costs and exemptions is available on the Department of Health's website.

Free Prescription Advice Line

This freephone advice line is open to patients to call with any queries about entitlement to exemptions or evidence of exemption. The number is 0800 91 77 711.

If unsure then pay the charge but ask for a receipt form FP57. If you are entitled to free prescriptions, you can claim the money back (within 3 months of receipt).