How to use
SessionOS

Set up your details and rates

Do this once. Everything here carries onto every invoice you ever send, so it's worth getting right before you log anything.

• Your name & trading asTrading name only if you invoice under one
  Required
• Address & emailAppears on the invoice header
  Required
• Account name, sort code, account numberHow you actually get paid
  Required
• VAT numberLeave blank if you're not registered
  Optional
• Default day rate & kit feePre-fills every new day — override per job
  Recommended
• Payment termsIn days. Sets the due date and drives chasing
  Recommended
• Invoice prefix & next numberFor example INV- starting at 001
  Recommended
• Upload logo & currencyGBP or USD
  Optional

Create your first job

A job is one booking for one client — however many days it runs. A three-day campaign is one job with three days, not three jobs.

• Client / brandWho is actually paying you
  Required
• Job titleFor example "SS27 campaign, day one"
  Required
• ContactName and email of the producer or booker
  Required
• Job reference / PO numberLarge brands won't pay without it
  If given
• Client billing addressAccounts department, not the studio
  Required
• Payment due afterOverrides your default for this client
  Optional

Add the days you worked

Every day is logged separately, so a job that grows mid-week just grows in the app. Add each day as it happens — the invoice builds itself from these.

• Date and day type — shoot, fitting, prep, test, travel or assist. Each is a real, billable day type, and naming it correctly is what lets a client see they booked you for two prep days as well as the shoot.
• Standard day, half day, or a custom fee — leave the fee blank to use your default, or type a figure to override it for this day only.
• Call time and wrap time — this is what drives your overtime multiplier and unsocial-hours multiplier. If you don't log the times, the app can't bill the hours.

Add expenses, kit and usage

These are the lines most artists forget, and each one is money you've already spent or already earned.

• Kit feeYour products, consumed on their job
  Per job
• MileageEnter the miles — the HMRC rate is applied for you
  Per journey
• ExpensesTravel, parking, couriers, materials bought in
  Itemised
• Assistant feeWhat you paid an assistant, recharged
  If used
• Usage feePlus the usage terms agreed in writing
  If licensed

Generate and send the invoice

SessionOS assembles the invoice from everything you've logged and assigns the next sequential number automatically — no gaps, no duplicates, which is exactly what HMRC expects of your numbering.

The PDF carries your logo, your bank details, the client's billing address, the PO number, every day and expense itemised, and the due date calculated from your payment terms. The text is selectable, so accounts departments can copy your bank details straight out of it.

• Check the preview before you send — particularly the PO number and the billing address, the two fields that cause the most payment delays.
• Use Email the contact to open it in your mail app with the invoice attached and the subject pre-filled.
• Mark it Sent. Nothing is chased until you do — the clock starts here.

Track payment and chase late invoices

Every job sits in one of three states, and the list shows you at a glance where your money is.

• Draft
  Logged but not invoiced — work you haven't billed yet
• Sent
  Invoiced and ageing against its due date
• Paid
  Settled, and counted in your earnings

When something goes past due, open the job and tap Chase by email. Choose the tone — polite, firm, or a formal reminder letter — and SessionOS drafts the message with the invoice number, amount and how many days overdue it is. Read it, adjust it, send it.

Export your tax-year statement

Earnings totals your income by UK tax year on a cash basis — counted when the money actually landed, not when you invoiced. That's the basis most self-employed artists file on, so the figure you see is the figure you declare.

Tap any total to drill into the jobs behind it, then export a statement PDF. Hand it to your accountant, or work from it directly for Self Assessment.

• Job Diary gives you the same year as a chronological record of days worked — useful for proving your working pattern.
• Clients shows every brand you've worked for with your rate history, and flags where you've charged one client less than another for the same work.
• Back up my data from the menu before any device change. Your data syncs to your account, but a backup costs you nothing.