There isn't such an offence.
While 'evasion' seems to fit the scenario's circumstances, 'council tax fraud' seems to be the more common term (an umbrella term). However:
While (generally) a person occupying a property is liable for council tax and if there is more than one person occupying the property then they are jointly and severally liable, there doesn't seem to be a duty to disclose that one is occupying a property.
You might imagine there must be a duty to disclose that you're occupying a property and some prosecutions have proceeded on that basis. But it seems there isn't such a duty, explicit or implied. See D, R. v (Rev 1) [2019] EWCA Crim 209 (05 February 2019):
So far as the proceedings in the Crown Court below are concerned, the judge expressed some surprise that there was no provision in the
statutory regime demonstrating an express obligation upon persons in
the position of the defendant to keep a local authority informed of
where such a person was living. Having raised this point, he gave the
prosecution more time to research the matter. Having been given such
time, and having no doubt further sought instructions from the local
authority itself, counsel still was unable to locate any express
provision of notification to this effect either in the 1992 Act or in
any statutory instrument made pursuant to it. But the position of the
prosecution remained that such obligation of notification was to be
statutorily implied.
At all events, it should also be made clear for present purposes that
the local authority in this case has also produced no evidence and no
document emanating from it by which persons resident within its area
are required to notify, or have agreed to notify, the local authority
of such residence for council tax purposes. Whether such an obligation
to notify could lawfully be imposed by a council by issuing some kind
of publication to that effect is not a matter on which we need express
any concluded view. The position does not arise in this case. The
position in the present case, on the assumed facts, therefore depends
solely upon whether as a matter of law such an obligation can be
statutorily implied.
The judge throughout was sympathetic to the local authority's
position. He clearly, and to an extent understandably, had concerns
that the absence of a duty to notify might provide, as the saying is,
a fast car and an open road to achieving successful fraud. In the
course of discussion, the judge reiterated his initial surprise that
there was not somewhere within the statutory provisions an obligation
to keep the local authority informed of the defendant's address.
Having so stated, he, as we have said, adjourned the matter for a
while to enable further research to be made. But that further research
achieved nothing. ...
- There can be no real doubt that on the assumed facts, and assuming that the defendant had herself been resident throughout at this property, as well as being its owner, she would have been legally obliged to pay the due amount of council tax. If she did not, the council could, on demand made under the statutory scheme, seek recovery of the sums due in the civil courts. But that cannot of itself, as we see it, connote that she was obliged in law to notify the council of her continued residence. It is quite wrong to equate a liability to pay with a liability to notify. It may be, as the judge thought, that one might have expected to find such a provision as to notification in the statutory scheme. But that was a matter for Parliament to decide. The fact is, as we have said, that such a provision simply is not there, either within the primary legislation or in subordinate legislation made pursuant to the provisions of the 1992 Act itself.
The council can come along and say you're liable for council tax. If for the purpose of paying less or no council tax you then provide false of misleading information you commit fraud or council tax fraud.
But you don't commit an offence of fraud when you don't tell the council you're occupying a property.
In england-and-wales there are council tax regulations for each nation that create specific criminal offences of council tax fraud.
Section 7 The Council Tax Reduction Schemes (Detection of Fraud and Enforcement) (England) Regulations 2013:
False representations for obtaining a reduction
7.—(1) If a person (P), for the purpose of obtaining a reduction under a council tax reduction scheme, whether for P or some other person—
(a) makes a statement or representation which P knows to be false; or
(b) provides, or knowingly causes or knowingly allows to be provided,
any document or information which P knows to be false in a material
particular,
P shall be guilty of an offence.
(2) A person guilty of an offence under this regulation shall be
liable on summary conviction to a fine not exceeding level 4 on the
standard scale, or to imprisonment for a term not exceeding 3 months,
or to both.
Section 7 The Council Tax Reduction Schemes (Detection of Fraud and Enforcement) (Wales) Regulations 2013:
False representations for obtaining a reduction
- A person (P) is to be guilty of an offence and liable on summary conviction to a fine not exceeding level 4 on the standard scale, or
to imprisonment for a term not exceeding 3 months, or to both if P,
for the purpose of obtaining a reduction under a council tax reduction
scheme whether for P or some other person—
(a)makes a statement or representation which P knows to be false; or
(b)provides, or knowingly causes or knowingly allows to be provided,
any document or information which P knows to be false.