Using EHIC card in Belgium

If you have permanently left the UK AND you are not in receipt of a UK state pension or long-term benefits, your UK-issued EHIC is no longer valid and you can obtain a replacement (for travel to other European countries including, currently, the UK) from your Belgian mutual. If, however, you are in receipt of a UK state pension or long term benefits, you will have received a form S1 which you take to the Belgian mutual of your choice and become adherents to that mutual (you will still have to pay the mutual a small charge each month) - the UK retains the responsibility in such cases for issuing you with an EHIC, at least at present.
The benefits that a UK visitor obtains from using an EHIC for emergency treatment are exactly on a par to the benefits you would obtain as a mutual adherent - BUT only for emergency treatment.
If you have become permanently resident in Belgium you will have to demonstrate adherence to a mutual (or evidence of more costly private health insurance) as a condition of registration.

as a resident of BE with public health insurance (= mutualité) the EHIC card is your confirmation of being registered to the mutualité and it's good for any doctor / hospital visits OUTSIDE Belgium but in the EU during your holidays (including Switzerland etc.)
see Here https://www.belgium.be/en/health/european_health_insurance_card
Attention: thus does not mean that the healthcare service provided in your holiday country is for free. Often you have to pay on the spot and you are getting the amount of the equivalent service in Belgium reimbursed.

EHIC itself cannot be used as a Belgian resident within Belgium!

Since you now seem to say that you ha

Since you now seem to say that you have joined a Belgian mutual (and are in the six month waiting period), you should ask these questions of your mutual. I have found mine most helpful.

You seem to be confusing what the European Health Card actually is. The card itself doesn't actually provide any cover.

The card merely confirms that you have health care coverage in your country of residence, and are therefore temporarily able to access healthcare in another EU country.

Innovator,
agree with Anon, and I thought my link provided explained what this card is for!
is your EHIC card issued by the BE mutualité? (or are you talking about another country's one?
If you have a valid EHIC card from BE, you can use it outisde BE and ATTENTION: it's only for emergency cases and not for planned doctor visits. These are the cases when refund problems start, when your mutualité has the feel it will be the latter.

Secondly, you have always to be aware, that BE is much less refunding than the emergency visits cost in your traveled country. An example: a dangerous wasp stitch cost us nearly 200 CHF, refund 28 EUR. End of story.
Get additional travel insurance, e.g. from Touring Belgium before leaving BE.

You are not from Brexit? Meaning?