Complaints Procedure
Version 2026.06. Effective 2 June 2026.
How we handle formal complaints
Mackenzie Costs aims to provide a high quality service. If something has gone wrong, please tell us so that we can put it right and improve what we do in the future.
We will not charge you for the time it takes us to handle your complaint.
How to complain
You may make a complaint in writing, by email, or by telephone.
- Contact: William Mackenzie
- Email: william@costlawyer.co.uk
- Telephone: 020 4576 8203
- Post: 66 Paul Street, London EC2A 4NE
What happens next
We will acknowledge your complaint in writing and try to do this within five business days.
We will investigate the complaint competently, diligently and impartially, keep a separate complaint record, and provide a written response within eight weeks of the date on which you first complained to us.
The Legal Ombudsman
If we have been unable to put things right, or we have not resolved your complaint within eight weeks, you may be able to ask the Legal Ombudsman to look at a service complaint independently.
If you have received our final response, you must take your complaint to the Legal Ombudsman within six months of that final response, and not later than one year from the date of the act or omission complained about, or one year from the date when you should reasonably have realised that there was cause for complaint.
- PO Box 6167, Slough SL1 0EH
- 0300 555 0333
- enquiries@legalombudsman.org.uk
- www.legalombudsman.org.uk
The Costs Lawyer Standards Board
William Mackenzie is regulated as a Costs Lawyer by the Costs Lawyer Standards Board (CLSB). The CLSB can investigate complaints about a Costs Lawyer's professional conduct.
The CLSB will ordinarily consider complaints made within 12 months of the relevant matter, or when the complainant first became aware that they had grounds for complaint. This period can be extended in exceptional circumstances.
- PO Box 4336, Manchester M61 0BW
- 0161 956 8969
- enquiries@clsb.info
- www.clsb.info
Alternative dispute resolution
If you are a consumer and our first-tier complaints process has been exhausted, there are approved alternative dispute resolution bodies that may be able to consider a complaint if both you and we agree to use them. Generally, we do not agree to use an ADR scheme because the Legal Ombudsman is the appropriate independent body for service complaints about legal services.
Contact Mackenzie Costs