Check that the advert falls within the remit of the ASA.
Read Writing a complaint
If you have an electronic copy of the advert, it is easy to submit it to the ASA using their online form.
If you only have a paper copy of the advert, you can submit it by post.
If you use the online form, select 'Internet' for 'Type of advertisement' and 'Claims on marketers' own websites' for 'SubType'. If you are submitting it by post, look at the web form and ensure you supply all the information it asks for. This templatedocument is useful while writing your complaint off-line and keeping a record of it (the ASA don't send you a copy of your complaint if you use the online form). You can then copy and paste the text into the online form.
You will receive a confirmation letter or email (this may take a few days or longer) and it will give you a reference number for your complaint, which you should take note of and use in any correspondence with the ASA about your complaint. There is space at the top of the document to record the ASA's reference number.
However, the confirmation doesn't tell you anything about what you submitted, so it can be confusing if you have submitted more than one complaint. It is therefore important that you keep a copy of what you submitted.
The best way to describe how to write a complaint is to show some examples.
A simple complaint about claims made by a chiropractor:
The advert states:
"Chiropractic can successfully treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying."
I doubt that the advertiser can substantiate those claims.
A longer complaint:
The advert says: 'Authentic and effective Kerala ayurvedic treatments'.
I doubt they could substantiate the claim that their Ayurvedic treatments are effective for any of the claimed conditions.
They advert also says: 'Qualified and registered Ayurvedic physicians'.
I am not aware that there are any registration bodies, statutory or otherwise, in the UK, so this claim may lead some to understand that the Kerala Ayurvedic Health Clinic practitioners are registered with a regulatory body that guarantees the quality and effectiveness of the treatments, perhaps with a code of practice.
This claim also says their practitioners are 'physicians', which will be understood by many to mean that they are medically qualified and GMC registered doctors. Since I doubt their practitioners are medically qualified or GMC registered doctors, this claim is misleading and I doubt they could substantiate it.
The claim 'Massage therapies by experienced and highly skilled therapists' may lead some to understand that the massage will be given by a trained physiotherapist. I doubt they could substantiate this.
The advert claims that 'Treatment is designed around your individual health needs'.
Since I doubt that their practitioners are medically qualified, I doubt that they can substantiate that their treatments are 'designed around your health needs' and that they are not qualified to make health decisions.
They claim 'Only natural herbal medicines are used'. I believe many herbal preparations are not 'natural' (ie some are chemically processed) and can also contain medically active prescription-only medicines and dangerous contaminants. I therefore doubt they could substantiate that their products are entirely natural.
The use of the word 'medicines' will be understood by many that they are clinically effective and I doubt they can provide evidence that would substantiate this.
The advert gives a list of 18 medical conditions, some of which are serious medical conditions and I doubt they could substantiate the efficacy of their treatments for any of these conditions.
I believe that the claims made and the overall tone of the advert will lead many to understand that their treatments are medically effective and proven and may dissuade or delay a reader from seeking proper medical advice and treatment.
This resulted in an ASA Adjudication on Kerala Ayurvedic Health Clinic (cached).
Simon Perry has written an excellent blog post: A Step-by-Step ASA complaint