A BMA handbook to support practices setting up the networks - which all practices in England are expected to join by July this year - shows funding the organisations can expect to receive in the coming financial year.
Most primary care networks (PCNs) are expected to cover patient populations of between 30,000 and 50,000. PCNs at the lower end of this scale will receive around £135,000, with those at the upper end expected to receive just over £180,000, the BMA guidance says.
Larger networks covering as many as 100,000 patients - which are expected to be rare - could receive more than £360,000 in 2019/20, according to a sliding scale set out in the guidance.
The handbook sets out how PCNs can elect or appoint a clinical lead, and outlines a range of operational models that practices setting up networks can consider. Some PCNs may operate with a 'flat' structure, while others could have a lead practice that takes primary responsibility for hiring new network staff and holding contracts taken on by the group.
The guidance says that setting up limited liability companies is an attractive option to keep individual pracitces at arms length from the considerable financial risk associated with employing new staff through networks - but warns that until NHS rules can be changed this could mean staff cannot be offered an NHS pension.
The handbook also raises concerns over structures that could mean practices are liable to pay VAT on services involving providing healthcare or back-office staff.
Funding for PCNs will include a £1.50 network administration payment per patient, funding for a clinical director appointed by the PCN, 70% reimbursement for a pharmacist and 100% reimbursement for a social prescribing link worker.
PCNs will also receive extended hours funding worth £1.45 per patient transferred from the current extended hours DES.
BMA GP committee chair Dr Richard Vautrey said: 'This year’s agreement between ourselves and NHS England contained some of the most significant changes to the GP contract in the last 15 years – most notably with the development of PCNs.
'The creation of PCNs, which delivers an additional £1.8bn in funding over five years, will offer tangible benefits and improvements to patients, GPs and the wider practice team through an expanded workforce to help reduce workload, and the BMA has been working hard to ensure that this process protects what makes British general practice so unique and valued.
'At their core, primary care networks will help practices work together in a local area so that patients can access the best possible care from within their communities, and from a range of healthcare professionals.
'There will understandably be many questions from practices as we approach July, and therefore we have produced this guidance to offer practical advice to GPs and their teams as they begin to establish networks that are right for them and their patients.
'Many practices will already be working collaboratively, through informal networks, and we hope that our guidance will help them formalise these agreements to receive the full benefits of this year’s contract changes.'