In the UK, 0500 numbers are old-style freephone numbers that are due to be withdrawn.
The majority of freephone numbers now begin with 0800 and 0808, making the 0500 prefix obsolete.
Withdrawal of 0500 numbers
0500 numbers will cease operation on 3rd June 2017.
Companies still using 0500 numbers can request that their number migrates to the 0808 prefix, or may use a completely new number depending on their requirements.
Where the migration option is chosen, the old 0500 xxxxxx number will migrate to 0808 5xx xxxx.
0500 number call costs
0500 numbers are intended to be free to call and generally remain so from landline telephones including payphones, although most mobile phone companies will charge for calls.