Best Invoicing Tools for Indie Hackers in 2026

Invoicing is one of those categories where the honest answer is often "you might not need a dedicated tool at all." But once you're past a handful of clients, or you want recurring billing, late-payment reminders, and something that looks more professional than a PDF you typed by hand, a real tool earns its keep. Here are three that take genuinely different approaches, plus the case for skipping all of them.

The three picks below aren't interchangeable. Invoice Ninja is the developer-friendly, open-source option with a genuine self-hosted path. Refrens is built primarily for the Indian market and its tax compliance requirements. Bonsai bundles invoicing into a broader freelance-operations platform rather than treating it as a standalone product. Which one fits depends less on which has more features and more on which of those three starting assumptions matches your actual situation.

Quick Verdict

Invoice Ninja

Invoice Ninja is open source, has been around since 2014, and is genuinely built for the developer crowd: full API access, a self-hosted option with no artificial limits, and integrations with Zapier, Make, and n8n on every plan including free. Payment gateway support runs deep too, with 15-plus options including Stripe, PayPal, Square, and GoCardless, so switching processors later doesn't mean switching invoicing tools.

Confirmed from Invoice Ninja's own pricing page: the Free plan covers up to 5 clients with unlimited invoicing, 4 invoice templates, recurring and auto-billing, product and inventory management, and a client payment portal, all at $0 forever, no credit card required. Ninja Pro is $14 a month billed monthly (or $140 a year, working out to $11.67 a month), unlocking unlimited clients and invoices, 11 templates, REST API access, automated late-payment reminder emails, and reports covering invoices, expenses, and profit and loss. Enterprise scales by account users, from $18 a month for 1-2 users up to $300 a month for 51-100 users, adding user permissions, bank sync via Yodlee or GoCardless, and e-invoicing with PEPPOL network access. Premium Business is custom pricing starting from $280 a year, adding a developer concierge and priority support.

The self-hosted route is worth calling out specifically. Because the codebase is open source on GitHub, you can run Invoice Ninja on your own server for free forever, with no client cap and no feature gate, the paid cloud tiers exist purely for convenience, not for access to core functionality. For a developer already comfortable running a Docker container, that's a genuinely free path to the full product.

Who should skip it: if you specifically need deep GST or regional tax compliance features, Invoice Ninja's tax handling is more generic than Refrens's India-focused tooling. Skip self-hosting too if you don't want the ongoing maintenance, in which case the $14-a-month cloud plan is the more realistic comparison point.

Refrens

Refrens is built primarily for the Indian market, and it shows in the product: a large share of its feature set and paid tiers are structured around GST compliance, e-invoices with IRN generation, e-way bills, and automated GSTR-1 and GSTR-3B reports. Beyond compliance, it also handles quotations, purchase and vendor management, and basic bookkeeping, positioning itself as more of a full accounting platform than a pure invoicing tool.

Confirmed from Refrens's own pricing page: the free Basic plan allows 15 documents a month (invoices, quotes, and other document types combined) with 2 users, at ₹0 forever, no commitment required. Accounts Lite, explicitly positioned "for solo founders, newly started businesses," runs roughly ₹492 a month effective on a 1-year plan, about $5 at current exchange rates, adding unlimited documents, branding removal, WhatsApp sharing, recurring invoices, and multi-currency support. Accounts Pro steps up to roughly ₹1,250 a month effective, adding the GST-specific features: e-way bills, e-invoices, GSTR reports, and bank reconciliation, along with basic roles and permissions for a small team. Higher tiers (Workflows, Operations) add approval chains and inventory management, aimed more at small businesses than solo freelancers.

The document-count cap on the free tier is worth understanding before you rely on it. Unlike Invoice Ninja's free plan, which caps by client count, Refrens caps by total documents a month, so if you're also sending quotes or proformas alongside invoices, you'll hit that ceiling faster than the invoice count alone suggests. Multi-currency support is included even on the entry paid tier, which matters if you're invoicing clients outside India in USD or EUR.

Who should skip it: if you don't invoice Indian clients or handle GST filing, most of what differentiates Refrens's paid tiers from a generic invoicing tool won't apply to you, and you're paying for compliance features you'll never touch. Skip the free tier specifically if you send more than a handful of documents a month combined.

Bonsai

Bonsai bundles invoicing into a broader freelance operations platform: proposals, contracts, a client portal, time tracking, and expense tracking all live in the same product, aimed at freelancers who want one subscription instead of four separate tools stitched together.

Confirmed from Bonsai's own pricing page: there's no free tier, just a 7-day trial requiring a credit card upfront. Basic is $9 a month per user billed annually ($15 monthly), but it does not include invoicing at all, just time tracking, task management, a CRM, and a service library. Essentials, the actual entry point for invoicing, is $19 a month per user billed annually ($25 monthly), adding invoices and payments, proposals, contracts, all templates, forms, scheduling, and a client portal. Premium, Bonsai's most popular tier, runs $29 a month per user billed annually ($39 monthly), adding project insights, workload management, a Gantt view, a deals pipeline, profit and productivity reports, and integrations with QuickBooks, Zapier, Calendly, and Google. Elite requires a 3-user minimum at $49 a month per user billed annually, adding custom permissions and a Xero integration.

The Basic-tier gap catches people out, and it's worth flagging explicitly. Because Bonsai's cheapest advertised price doesn't actually include invoicing, the realistic starting cost for what this post is about is Essentials at $19 a month, not the $9 headline number that shows up first on the pricing page. Payment processing fees also apply on top of the subscription whenever a client pays by card, ACH, or PayPal, which is standard for the category but worth budgeting for separately.

Who should skip it: if invoicing is genuinely the only thing you need, Bonsai's per-user pricing for a bundle of features you may not use is hard to justify against a dedicated tool. It's a stronger fit specifically if you also want proposals and contracts in the same place, replacing several separate subscriptions rather than just one.

Do You Actually Need a Separate Tool?

If you already accept payments through Stripe, its built-in Invoicing feature is worth checking before you subscribe to anything. There's no monthly fee: Stripe charges 0.4% per paid invoice on the Starter tier (0.5% on Plus), capped at $2 regardless of invoice size, plus normal card processing if the client pays by card. In a worked example of 10 clients and 10 invoices a month at $500 each, that lands around $20 a month, comparable to Invoice Ninja's Ninja Pro at $14 or Bonsai's Essentials at $19, and cheaper than all three at lower volume since you only pay when an invoice actually gets paid, never a flat subscription sitting idle in a quiet month.

The tradeoff is real, though. Stripe's invoicing tooling is thinner than a dedicated tool on things like quotes, expense tracking, and recurring billing across dozens of clients at once, and the per-invoice fee scales with your volume in a way a flat subscription doesn't. If you've already gone through our Lemon Squeezy vs Stripe vs Paddle comparison, the same logic applies here: whichever processor you're already using probably has invoicing built in, and adding a second subscription only makes sense once you need something the processor doesn't offer, like a proper quotes-to-invoice workflow or GST-specific compliance.

Which Invoicing Tool Should You Actually Use?

For most solo indie hackers, start with Invoice Ninja. The free tier covers small client lists, Ninja Pro is cheap once you outgrow it, and the self-hosted option means you're never locked into a subscription if you'd rather run it yourself and own your invoice data outright. Pick Refrens specifically if you invoice Indian clients and need GST compliance built in, since that's the market it's actually built for, and its higher tiers will feel like overkill everywhere else. Reach for Bonsai only if you want invoicing bundled with proposals and contracts in one subscription, and budget for Essentials rather than the cheaper Basic tier that doesn't include invoicing at all. And before paying for any of them, check what your existing payment processor already gives you for free or near-free. If you're still deciding between processors in the first place, our Stripe alternatives roundup and Lemon Squeezy alternatives post cover that decision directly, and either choice will shape which invoicing option actually makes sense for you.