Not always, but it’s strongly recommended. We can proceed with your unpaid invoices and supporting records even if you don’t have a signed engagement letter, as long as there is clear evidence the work was requested and delivered. For accounting and bookkeeping firms, this usually includes things like email approval, scope documents, timesheets, completed BAS/lodgement records, or a history of ongoing work. The clearer the paper trail, the easier it is for us to establish liability and recover the debt quickly. If you do have a formal service agreement in place, that simply strengthens your position and helps resolve disputes faster, but it isn’t mandatory for us to begin the recovery process.