Ignition

The decision Ignition forces on a firm is the useful one. A client who accepts a proposal signs the engagement letter and hands over a card or bank account in the same sitting, and from that point the billing schedule runs without anyone in the firm raising an invoice. A monthly bookkeeping package charges on the first, a tax return charges on delivery, an out-of-scope request becomes a change to the live agreement rather than an awkward email. Draft invoices land in QuickBooks Online or Xero so the ledger matches what was collected. Ignition is unambiguously the payments half of this category, and a firm that only wants a signature is buying the wrong product.

That makes the payment economics, not the subscription, the number that matters. Subscriptions run from $39 a month on Solo for 20 active clients and one user up to $399 on Pro+ for 600 clients and unlimited users, all billed annually, with per-client overages of $7 down to $2. Processing is charged separately: 2.5% plus $0.30 on Visa and Mastercard, 3.6% plus $0.30 on Amex and corporate cards, and 1% plus $0.30 on ACH capped at $5, with an extra 0.3% above $3,000. On $400,000 of annual collections split evenly, the ACH cap is what keeps the bill sane, and a firm that lets clients default to Amex will pay several times the subscription in processing.

The templates are the other thing worth checking before signing. Ignition's engagement letter terms come through partnerships with the National Association of Tax Professionals and the National Association of Enrolled Agents, and the proposal library was built with practitioners including Josh Lance and Ryan Lazanis. That is a real answer to who wrote the language, better than most of this category offers. The vendor does not publish how often those terms are reviewed, so a firm relying on them should still have its own counsel or insurer look once.

Where it strains is at the edges of a practice. Ignition is not practice management, so work still has to be tracked somewhere else, and the Karbon and TaxDome connections carry the client rather than the job. The client-count bands are unforgiving for a firm with a long tail of small one-off returns, since a dormant 1040 client still counts. And because the proposal, the letter and the payment authorization are one artifact, a firm that wants a lawyer-reviewed letter separate from a pricing document will find the model rigid. Knuula exists for exactly that firm.

Against Anchor, the choice is cost shape rather than capability: Anchor charges nothing monthly and $5 a payment, which favors a firm with few large invoices, while Ignition's banded subscription with a $5 ACH cap favors a firm with many small recurring ones. Against Cone, Ignition brings the deeper US tax integrations and a longer track record. Top pick stands. SOC 2 Type 2, US-hosted data, 8,500 customers claimed, offices across the US and a template library co-authored with two national tax associations is the strongest evidence base in this category.