InvoiceFlowby StackQuil

Documentation

Getting started

Create a free account, then complete Settings: legal name, address, state and (if registered) GSTIN. Your state decides whether a supply is intra-state (CGST + SGST) or inter-state (IGST). Add clients and save the services you sell in Products & Services.

Want to look around first? Explore the demo opens a private sample workspace for 24 hours.

Quotations & versions

  • A new quotation is a draft — edit freely.
  • Finalise & send freezes it as version 1. The client always sees a frozen version.
  • To change a sent quotation, choose Revise: version 2 opens as a draft, version 1 stays on record. Send again when ready.
  • Accepted quotations can't be revised — the agreed terms are final. Duplicate to start a new one.
  • Quotations past their valid-until date move to Expired and can't be accepted.

Client approval links

On Pro and Agency, Client link creates a secure, unguessable URL (256-bit random, stored only as a hash). Clients don't need an account. To accept or decline they must type their name and tick a confirmation box; each decision records the version, time and comment. Opening or downloading never counts as acceptance. Links expire (30 days after the validity date for quotations, 180 days for invoices) and can be revoked from the document page.

“Viewed” is set only when the link is opened by someone who is not signed in as a member of your workspace.

Invoices

  • Create an invoice directly, or Convert to invoice from an accepted quotation. Conversion copies the accepted version and is blocked from happening twice.
  • If the quotation asked for an advance, you can bill an advance invoice first and a balance invoice later. These are created as single summary lines priced tax-inclusive — review the draft, especially if the quotation mixed GST rates.
  • Drafts have no number. Issue assigns the next number (server-side, in sequence, never reused) and locks the invoice with a snapshot of your business and client details.
  • To correct an issued invoice: reverse any payments, Cancel it with a reason (the number stays on record), then duplicate and issue a corrected one. Credit notes aren't supported yet.
  • Overdue is calculated from the due date in your business timezone.

How GST is calculated

All amounts are integers in paise; nothing uses floating-point arithmetic. For each document:

  1. Line amount = quantity × rate, rounded to the paisa (half-up).
  2. A document discount (fixed or %) is spread across lines in proportion to their amounts, before tax.
  3. Only lines marked Taxable attract GST. Exempt, nil-rated, zero-rated and non-GST lines are shown separately at 0%.
  4. Intra-state: CGST and SGST are each half the rate, rounded per line. Inter-state (including exports, place of supply 96): IGST at the full rate.
  5. Tax-inclusive prices are split back into taxable value and tax so the line total stays exactly what you entered.
  6. Optional round-off to the nearest rupee is shown as its own line.

Important: InvoiceFlow is a calculation and document tool. It checks a GSTIN's format and checksum but doesn't verify registration, doesn't file returns, and doesn't generate e-invoice IRNs or e-way bills. Reverse charge isn't modelled. Confirm the correct rate and treatment for each supply with your tax adviser.

Recording payments

Open an issued invoice and choose Record payment. Partial payments are fine; amounts above the outstanding balance are refused. Each payment gets a receipt number and a downloadable receipt. A double-clicked or retried submission is recorded once. Mistakes are fixed with Reverse (admins and owners), which keeps the record marked reversed and restores the balance.

InvoiceFlow never marks an invoice paid because a client opened a link or returned from a checkout page.

Reports & metrics

  • Received — recorded, non-reversed payments dated in the period.
  • Invoiced — issued invoices (not drafts or cancelled) dated in the period.
  • Outstanding — unpaid balance of open invoices today.
  • Acceptance rate — accepted ÷ sent, for quotations issued in the period.

Pro features

  • UPI scan-to-pay — add your UPI ID in Settings. INR invoices with a balance show a QR (and an “Open UPI app” button on phones) pre-filled with the balance and invoice number, on the PDF and the client link. UPI apps don't confirm payments back, so record the payment when it arrives.
  • Recurring invoices — weekly, monthly, quarterly or yearly. Each run creates a draft or issues automatically. Missed dates are caught up the next time the app is used; a date is never billed twice. Month-end start dates stay anchored (31 Jan → 28 Feb → 31 Mar).
  • Client statements — from a client page, download a PDF with opening balance, invoices, payments and closing balance for any period.
  • Quotation templates — “Save as template” on any quotation; pick it when creating a new quotation.
  • Insights — average days to get paid, on-time rate and average time to a client decision, over the last 12 months.
  • ⌘K / Ctrl+K (every plan) — search clients, quotations and invoices or jump to any page.

Import, export & your data

Import clients from CSV with a preview and duplicate check; existing clients are never overwritten. Export clients, invoices, payments and quotations as CSV (formula-safe). Account & data downloads a full JSON export. Deleting your account permanently deletes the workspaces you own.

Backups of the hosted database are the operator's responsibility — keep your own exports for important records.

Plans & limits

Limits apply to creating new clients and documents. After a downgrade, everything you already have stays available; paid features pause. See Pricing.