A boarder is a lodger who receives food or meals, as well as accommodation. As for what is a lodger …
In most of the cases in which the superior courts have considered this question, they have distinguished common law tenants from lodgers on the basis that common law tenants have a right to occupy exclusively, while lodgers have a right to occupy that is not exclusive. The Residential Tenancies Act 2010 (NSW) (the RT Act), however, provides that an agreement for a right to occupy that is not exclusive may be covered, while a lodger’s agreement is not covered. Apparently the RT Act 2010 has in mind that lodgers have a defining characteristic other than a non-exclusive right to occupy, but the Act does not say what that defining characteristic is.
The caselaw does, however, indicate some other incidental characteristics of lodgers’ agreements. In Noblett & Mansfield v Manley  SASR 155, the South Australian Supreme Court characterised a lodger as ‘one who resides as an inmate in another person’s house’, while the landlord ‘retains control over rooms and means of ingress and egress’. In Street v Mountford  2 AC 809, the British House of Lords observed that a lodger’s landlord provides ‘attendance or services’, where a tenant’s landlord does not.
In Commissioner for Fair Trading v Voulon  WASC 229, the Western Australian Supreme Court used these incidental characteristics to set out a definition of ‘lodger’, as distinct from a tenant under residential tenancies legislation who has a right to occupy non-exclusively:
The decided cases indicate that an occupier of residential accommodation at a rent for a term is either a lodger or a tenant. The occupier is a lodger if the landlord provides attendance or services which require the landlord or his servants to exercise unrestricted access to and use of the premises. In other words, a lodger is entitled to live in the premises but cannot call the place his own. he resides essentially as an inmate in another person’s house.
In determining whether an occupier is a lodger or a tenant, the Tribunal has considered factors such as whether the landlord or caretaker lives at the premises (tends to indicate a lodgement), whether the occupier can lock the door to their room (tends to indicate a tenancy), whether there are any ‘house rules’ (tends to indicate a lodgement) and whether the landlord provides cleaning services, linen, newspapers or milk (tends to indicate a lodgement). There is no single factor that always determines whether an occupier is lodger or a tenant.
Finally, an occupier is not a lodger merely because their agreement calls them a lodger. It is the substance of the right to occupy that matters, not the form of the agreement (Radaich v Smith  HCA 45).
Lodgers in registrable boarding houses
If you live in a registrable boarding house under the Boarding Houses Act 2012 (NSW) (the BH Act), the question of whether you are a lodger or a tenant is still relevant to you. The definition and factors discussed above should be considered in determining whether you are a lodger or a tenant.
However, if according to these factors you are a lodger, the BH Act will provide that you have an occupancy agreement consistent with the ‘occupancy principles’ set out in the BH Act, and access to dispute resolution in the NSW Civil and Administrative Tribunal. Your occupancy agreement will probably refer to you as a ‘resident’ rather than a ‘lodger’, reflecting the terms used in the BH Act.
See the section on Boarding houses for more about the BH Act and registrable boarding houses. Note that at March 2013, most of the BH Act, including the provisions relating to occupancy agreements, has yet to commence.
This is new
Prior to the BH Act, boarding house residents who were lodgers had common law lodging agreements only.