
2 December 2020
Hearing aid types
Learn about the pros and cons of different types of hearing aids so you can find one suited to your needs.

In this article
Hearing aids are small devices that fit in or behind your ear and can help you to hear sound louder and more clearly. They are battery-operated and have a microphone that picks up the sounds around you. These sounds are processed and amplified electronically, passed on to a receiver and converted back into sounds that you can hear.
Hearing-aid technology has improved considerably in recent years. Most, including all NHS hearing aids, are now digital. This means they can be quite accurately personalised to your hearing loss.
Your audiologist should discuss which brand they're recommending for you and why, and explain the pros and cons.
- If you decide to get a hearing aid privately, our guide to the best and worst hearing aid providers will help you choose where to go for yours.
Are smaller hearing aids better?
Many people believe that small hearing aids that fit in your ear are pricier, more up to date and ‘better’ – but in fact, any size and type of hearing aid can be the modern, digital kind.
Some smaller hearing aids can be difficult to manipulate if you have poor eyesight or dexterity. They can sometimes be a bit harder to keep clean and can be more affected by heat and moisture, as the mechanics of the hearing aid sit in the ear canal. They are usually only suited to people with mild to moderate hearing loss.
In our 2020 survey of 1,572 Which? members and other adults, only 6% of those who paid privately got 'invisible' hearing aids. The most common were behind-the-ear open-fit, bought by 49% of our respondents.
Despite looking more discreet, invisible hearing aids are not necessarily more expensive than other types. What the hearing aid looks like has no bearing on the cost, as it’s the technology that’s important. Our guide to hearing aid prices shows how much you can expect to pay, based on the features you need.
Less common types of hearing aids
Hearing aid with tinnitus masker
These are designed to mask the presence of tinnitus. They don't always bring long-term relief though.
Bone conduction hearing aids
These are suitable if problems with your outer or middle ear are stopping sound from getting through. They send sound vibrations through the skull directly to the inner ear. They can be worn with a headband or attached to your glasses and some are surgically implanted (see 'Implantable devices', below).
CROS and BiCROS hearing aids (contralateral routing of signals)
CROS hearing aids are suitable if you have hearing in one ear only. They pick up sounds from the side with no hearing and transmit it to your better ear. BiCROS aids amplify sound from both sides and feed it into the ear that has better hearing.
Audiologists traditionally fitted CROS or BiCROS hearing aids on spectacles to hide all the wiring. However, thanks to today's wireless technology, this is no longer necessary.
Body-worn analogue hearing aids
These may be useful if you have a visual impairment or find it hard to use small switches or buttons. Some can be very powerful. They’re not widely available anymore as they’re so bulky (a small box containing the microphone and working parts is connected by a lead to an earphone clipped into your earmould, and the box is clipped on to your clothes – it’s about the size of a small mobile phone).
Custom-made spectacle hearing aids
It’s possible to have your hearing aids and glasses built into one unit. However, this generally isn't ideal: if your hearing aids need repairing or you need a new glasses prescription, you could be left with neither hearing nor visual aids in the interim.
With some spectacle aids, the frame has to be adapted or cut, meaning that the glasses can’t be returned to their original state. Once the hearing aid has been fitted to the frames, some opticians are reluctant to change the lenses in the glasses as they are worried about damaging the hearing aid. Also, the hearing aids can’t be removed and worn separately.
Due to low demand, the technology in spectacle hearing aids can be slightly behind normal hearing aid technology, despite costing about the same.
However, one instance where spectacle hearing aids can work really well is if you have conductive hearing loss. This is because the bone conductor is mounted onto the arm of the glasses and creates pressure on the mastoid bone behind the ear, transferring it directly to the cochlea in the inner ear.
They can also be useful for people who have mild to moderate hearing loss, but are unable to wear any device in or around the ear due to allergy or infection.
Implantable devices
If a standard hearing aid really isn’t suitable for you, either because your loss is too severe for you to benefit or you are unable to wear one, you still have options, including cochlear implants and bone-anchored hearing aids (BAHAs).
Cochlear implants are small electronic devices that give you the sensation of sound. They comprise an external part worn like a hearing aid and an internal part that is surgically implanted into your inner ear. The sound from the implant will take a little while to get used to (voices sound like Daleks) and you will need to be trained to understand what you are hearing.
BAHAs are digital bone-conducting devices that are fitted to a press-stud-like screw that has been inserted into the mastoid bone behind your ear. BAHAs are suited to people whose hearing is reduced by problems with their middle ear, such as infections. The sound is sent directly to the cochlear via the bones in the skull.

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