Invoice Simple alternative for UK builders: EstiMate compared

Invoice Simple does one thing well. It gets an invoice out of your phone and onto your client's screen with a pay button on it. If you're a freelancer, a handyman doing one-visit jobs or a sole trader sending a few invoices a month, it's a sensible choice and you can stop reading here.

If you build extensions, fit kitchens or run loft conversions, the invoice is the last step of a long job. Before it come the take-off, the price, the quote the client agrees to, the contract, the variations, the stage payments and the CIS on your subbies. That's the part EstiMate is built for, and it's the part an invoice app was never meant to do.

So: freelancers and one-visit trades, Invoice Simple is fine. Builders who quote, contract and run projects, here's the detail.

Invoice Simple is a very good invoice app. That's the problem.

Credit first. Invoice Simple is a mobile-first invoicing and payments app for freelancers and small businesses, covering estimates, invoices, receipts and card payments, and it isn't trade-specific (Invoice Simple). It's based in Vancouver (about Invoice Simple). On the UK App Store it scored 4.8 out of 5 from about 29,000 ratings in an older snapshot (App Store). That's a lot of people who like it.

Estimates are unlimited on every plan (Essentials plan), every plan takes online payments, and you can pass the card fee on to your client (pricing). There's also "Quick Invoices with AI", which builds an invoice from a short typed or spoken prompt (features).

The trouble is that a building job rarely goes wrong at the invoice. It goes wrong at the price, the scope and the extras nobody wrote down.

Their signature, their words

This is the bit to read twice. On Invoice Simple's Premium plan your client can sign an estimate (help centre). But Invoice Simple's own help centre says the client signature "is intended for presentation purposes only and should not be considered a legally binding contract" (help centre).

That's honest of them, and it's fine for a logo design or a one-day repair. It isn't what you want behind a £45,000 extension when the client disputes the third stage payment.

In EstiMate, the accepted quote turns into a contract covering payment terms, delays, responsibilities, insurance, guarantee and dispute wording. The client signs it online, and every variation becomes a signed addendum to it. More on that at construction contract software.

Ten invoices a month goes quickly on a building job

Invoice Simple's lower plans cap your invoices. Here's what its pricing page shows.

Prices checked October 2026 on Invoice Simple's pricing page, which shows US dollars and says prices "may vary by local currency". We couldn't confirm the UK price in pounds or whether VAT is included, so check the App Store on your phone before you subscribe. EstiMate is £15.99 a month per business, and the prices on our pricing page are what you pay, with a VAT receipt for every payment.

Now count invoices the way a builder does. Take an illustrative kitchen fit: a deposit invoice, a stage payment when the units go in, another when the worktops are templated, and a final. That's four invoices for one job. Run three kitchens in a month and you've sent twelve, which is past the Plus plan's ten, so on Invoice Simple you're on Premium. There's more on the sums in our Invoice Simple pricing guide.

What a builder needs, side by side

"Not found" means we searched Invoice Simple's site and help centre in October 2026 and found nothing; "not confirmed" means we couldn't confirm it either way. Neither proves the feature is missing, so ask them if it matters to you. On EstiMate, the quote link, contracts, variations, invoicing and the Accounts tab are on the £15.99 plan and above, and take-off is on Pro at £39.99.

CIS and the reverse charge

If you work as a subbie for a main contractor, your invoices need the CIS deduction shown and, where the domestic reverse charge applies, the reverse-charge wording. We couldn't find either in Invoice Simple; its site says it "adds VAT and discounts for you" (Invoice Simple customers page). Its Bookkeeping add-on, with a bank feed, P&L and balance sheet, is a paid add-on for US and Canadian users only (Bookkeeping announcement).

EstiMate works out the CIS deduction, logs it in a CIS register, and puts the required wording on reverse-charge invoices. On the £15.99 plan and above, the Accounts tab gives you a P&L for any period and the VAT figures for your return. It doesn't file anything to HMRC; it prepares the figures, and plenty of builders still have an accountant do the filing. If the reverse charge is new to you, read our reverse charge explainer.

Who Invoice Simple suits

• Freelancers and sole traders who send a few invoices a month and want nothing to learn.
• One-visit trades: a gutter clear, a lock change, a small repair.
• Anyone who mainly wants a phone app that takes card payments.

Go in with your eyes open on the account side. Capterra reviewers give it 3.7 out of 5 from 44 reviews, with a customer service sub-score of 3.1 (Capterra), and a recurring complaint on Trustpilot is that billing carried on after cancelling (Trustpilot).

Who EstiMate suits

• Builders and contractors whose jobs run for weeks, with stage payments and extras.
• Subbies and main contractors dealing with CIS and the reverse charge.
• Firms that want the price, the contract, the site records and the accounts in one place, priced per business rather than per invoice.

EstiMate comes out of a builder's office. Dave Groom, a tradesman who became a contracts manager, founded Tatton Projects, a design-and-build firm in Altrincham, and EstiMate began as the spreadsheet that firm quoted from.

How to switch

1. Start on EstiMate's free plan: no card, no time limit, three jobs a month with watermarked PDFs.
2. Price your next enquiry in EstiMate. The free plan gives you the material and labour breakdown and a watermarked PDF; the quote link, where the client can accept, decline, pick optional extras or ask for changes, starts on the £15.99 plan.
3. Finish the jobs you've already invoiced in Invoice Simple, and keep copies of those invoices for your records.
4. Move up to EstiMate at £15.99 a month when you need the quote link, contracts, invoicing, unlimited jobs and branded PDFs, then cancel Invoice Simple and keep the confirmation.

Send your next quote from EstiMate: start free.