Clamp vs Invoice Simple: A low-cost invoicing app, or one job record from estimate to final invoice
Invoice Simple is cheaper and simpler when all you need is to send estimates and invoices and get paid. Clamp is for the contractor who has outgrown that: estimates, contracts, change orders, invoices, job cost and mileage all kept on the job.
Direct answer: Invoice Simple Essentials is $6.99 a month or $69.99 a year for 3 invoices a month; Plus is $14.99 or $149.99 for 10; Premium is $21.99 or $219.99 for unlimited invoices. Clamp Solo is $19.99 a month or $149.99 a year with unlimited documents, plus change orders, job costing and mileage on the job. Choose Invoice Simple when sending invoices and taking payment is the whole job.
Proposal with milestones
Invoices on the schedule
Sample data. The proposal carries the milestone schedule the customer signs, and the invoices follow that schedule through the final payment.
What it costs
| Situation | Clamp | Invoice Simple |
|---|---|---|
| One person, up to 3 invoices a month | Solo, billed annually $12.50 a month $149.99 a year, calculated | Essentials, billed annually $5.83 a month $69.99 a year, calculated |
| One person, 4 to 10 invoices a month | Solo, billed annually $12.50 a month $149.99 a year, calculated | Plus, billed annually $12.50 a month $149.99 a year, calculated |
| One person, more than 10 invoices a month | Solo, billed annually $12.50 a month $149.99 a year, calculated | Premium, billed annually $18.33 a month $219.99 a year, calculated |
| One person who wants customers to sign in a portal | Assistant, billed annually $41.67 a month $499.99 a year, calculated | Premium, billed annually $18.33 a month $219.99 a year, calculated |
| A crew of 5 | Teams (up to 10 people), billed annually $83.33 a month $999.99 a year, calculated | No published multi-user plan Invoice Simple publishes no per-plan user count. |
Every Clamp feature, next to Invoice Simple
Solo includes 28 of Clamp's 44 features. Invoice Simple's pages show 7 of the 44 in full and 4 in part, across its plans.
Clamp plan
| Feature | Clamp | Invoice Simple |
|---|---|---|
| CRM and leads | 3 of 5 | 1 of 5 |
| Email remindersEmail reminders before appointments, follow-ups, and scheduled installs, deliveries, and inspections. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | ✓ Invoice due date reminders |
| Customer appointment remindersHomeowners get an email before an appointment, with confirm and reschedule built in. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Five-factor lead scoringA clear yes, no, or maybe on a lead before driving out. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Lead reportingClose rate, revenue won, open pipeline, close rate by lead source, and lost leads by reason, on Home and the stats screen, with CSV and PDF export. Revenue by source does not exist; see _excluded. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Daily briefingOverdue invoices, detected trips, follow-ups, appointments, and open proposals in one morning view. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Estimating | 7 of 7 | 2 of 7 |
| Design agreementsPaid preconstruction sits in the document chain, so planning work is paid work. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Itemized estimatesAssembly-based estimates with quantities and rates the contractor can inspect line by line. | ✓ Every planSolo, $12.50 a month billed annually | ✓ Unlimited estimates on paid plans |
| Estimate templatesSave an estimate as a template for work done often. | ✓ Every planSolo, $12.50 a month billed annually | ✓ Customizable estimate document templates |
| Proposals with multiple package tiersGood, better, best packages in one proposal. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| AI estimating from a plain-language job descriptionDescribe the job in plain words and get an itemized draft: assemblies, quantities, researched baseline rates, with the contractor's own saved rates taking over once set. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Remodel and new-home estimatingOne estimator covers remodels and new homes and detects which one a description is. Detect is the default job type; a contractor can pick Remodel or New home per estimate, or set Kind of work to Remodeling to turn the choice off. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Labor hours on estimatesEstimated labor hours, shown as a range, on every labor line, with an allowance for setup, cleanup, and material runs (15% by default) the contractor can change in Settings or per estimate. A planning figure; it never appears on proposals, PDFs, or the portal. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Contracts and invoicing | 5 of 5 | 3 of 5 |
| Payment schedulesSplit a proposal into a deposit, milestone payments, and a final payment, then invoice each one from the signed contract. | ✓ Every planSolo, $12.50 a month billed annually | ✓ Multiple scheduled invoice paymentsDocumented with Stripe; lowest subscription tier not stated. |
| Sales tax on documentsAdd a sales tax rate or a flat amount to invoices and other documents, with collected tax totaled by quarter and year. The contractor enters the rate; Clamp does not look rates up. | ✓ Every planSolo, $12.50 a month billed annually | ✓ Configurable document and item tax |
| Customer credits and refundsApply a customer's credit to an open invoice, record a refund, or adjust a balance, with the history kept on the job. Recorded only; Clamp moves no money. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Change orders that update the contractScope changes get written up and tied to the original contract, so verbal changes stop costing money. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Invoices tied to the contractEvery invoice belongs to the contract or change order it bills. | ✓ Every planSolo, $12.50 a month billed annually | ✓ Three invoices per monthPlus allows 10; Premium unlimited. |
| Customer portal | 0 of 6 | 0 of 6 |
| Password-free customer portalThe homeowner opens a link. No account, no password, no app to install. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Unlimited documents and photos shared to the portalShare job documents and photos to the customer portal without a count cap, subject to per-item size limits. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| E-signing on the homeowner's phoneDocuments get signed on the homeowner's own phone, no account required. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Presentation only client estimate signaturesVendor says not a legally binding contract; owner signatures start on Plus. |
| Several signers on one documentSend one document to up to five people, each signing their own line, see who has signed, and remind anyone who has not. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Project updates and decisions in the portalPost project updates to the customer's portal and ask the customer to make a decision, which they answer from their phone. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Not delivered email handlingWhen a customer email Clamp sends bounces, the document is marked Not delivered so the contractor can fix the address and resend, or copy the link to text it. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Expense tracking | 5 of 5 | 1 of 5 |
| Automatic GPS mileage trackingBackground trip detection, route maps, IRS rates, trips linked to the job that caused the drive. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Automatic time on siteGPS geofence tracking of hours at the jobsite. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Receipts and expenses on the jobReceipts logged against the job they belong to. | ✓ Every planSolo, $12.50 a month billed annually | ✓ Scanned receipts and expense recordsLowest tier not established. |
| Purchase ordersCommitted costs captured between the estimate and the receipt. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Accounts payable and vendor billsVendor bills tracked and surfaced in the attention flows, with first-class vendor records. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Job costing and reports | 3 of 3 | 0 of 3 |
| Job costingWhat the job actually cost, with a variance and catalog learning loop. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Accountant export packageA package of the business's records prepared for an accountant. | ✓ Every planSolo, $12.50 a month billed annually | Invoice and expense summary exportsPDF/XLSX/CSV, not verified estimate-to-actual job costing. |
| Time reporting with CSV exportReported labor time with a time-tracking CSV export for payroll preparation and per-person rate decomposition. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Jobsites and teams | 2 of 8 | 0 of 8 |
| Teams: up to 10 linked accountsUp to 10 accounts, including the owner, sharing one business. | ✓ TeamsTeams, $83.33 a month billed annually | Support added account email accessNo published per-plan seat count; this is not evidence of crew roles. |
| Role-based permissionsFive roles: owner, admin, staff, contributor, viewer. | ✓ TeamsTeams, $83.33 a month billed annually | Not found |
| Unlimited subcontractor linkingSubs share jobsite photos and notes into the business account without consuming a seat. | ✓ TeamsTeams, $83.33 a month billed annually | Not found |
| Jobsites tab: jobs and schedule in one placeA Jobsites tab with Jobs and Schedule views. With Assistant each job has its own screen with its schedule, photos, and updates, and the Schedule view holds every install, delivery, inspection, appointment, and follow-up; Teams adds the crew and subs on each job, shaped by role. Subs invited to a job use it free and see their own jobs grouped by builder. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Job scheduleSchedule installs, deliveries, and inspections on each job, with the contractor, a supplier, or nobody yet on each item, and see them all in the Jobsites tab. Putting crew or subs on an item is the Teams shared schedule. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Shared job scheduleOne schedule for the business: installs, deliveries, and inspections visible to the team, with clash notes when dates collide. | ✓ TeamsTeams, $83.33 a month billed annually | Not found |
| Punch listsThe small final items that close a job out, tracked per job and shareable as a text message or a PDF. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Job site photosPhotos saved to the project with full-screen viewing. | ✓ Every planSolo, $12.50 a month billed annually | Document photo attachmentsNo operational job-photo timeline verified. |
| Backup and offline | 3 of 5 | 0 of 5 |
| Full job workflow, offlineLeads, design agreements, estimates, proposals, change orders, and invoices on the phone, working without a connection. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| Cloud backupBusiness data backed up to the cloud and restorable on a new device. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Business portal: read-only web viewA read-only view of the business in a browser. | ✓ Assistant and TeamsAssistant, $41.67 a month billed annually | Not found |
| Device backup, restore, CSV export, bulk importLocal backup and restore with CSV export and bulk import. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
| No account required to startThe app opens to local use; an account is needed only for server features or subscribing. | ✓ Every planSolo, $12.50 a month billed annually | Not found |
Nothing here matches. Pick All or another filter.
Invoice Simple column from its pricing page, feature pages and help center, checked October 15, 2026. Not found means not on those pages, not that Invoice Simple can't do it another way. Partly means something narrower than the Clamp feature. No product was tested against another.
Where each Invoice Simple answer comes from
- Pricing plans and packages Invoice Simple, accessed October 15, 2026
- Premium pricing and full plan comparison Invoice Simple, accessed October 15, 2026
- Official information about Invoice Simple Invoice Simple, accessed October 15, 2026
- Payments fee schedule Invoice Simple, accessed October 15, 2026
- How do I schedule a payment? Invoice Simple, accessed October 15, 2026
- Is the client signature legally binding? Invoice Simple, accessed October 15, 2026
- How do I keep a record of expenses? Invoice Simple, accessed October 15, 2026
- Export invoice or expense summaries Invoice Simple, accessed October 15, 2026
- Give someone else access to an account Invoice Simple, accessed October 15, 2026
- Set taxes on invoices and estimates Invoice Simple, accessed October 15, 2026
- Invoice Simple features Invoice Simple, accessed October 15, 2026
- Set up Bookkeeping with Invoice Simple Invoice Simple, accessed October 15, 2026
- Financial reports with Bookkeeping Invoice Simple, accessed October 15, 2026
Verdict
Clamp may fit when
- You send more than a few invoices a month and are hitting a plan's invoice limit
- Your scope changes after the contract and you want each change priced, signed and billed as its own change order
- You want customers to sign proposals and change orders in a customer portal, not a signature added for presentation
- You track receipts, vendor bills, time on site and labor against the estimate and review job cost at close
- You want business mileage logged automatically and tied to your jobs
- You are adding a helper or a crew and need separate accounts, with subs who never see your prices
Invoice Simple may fit when
- You send 3 or fewer invoices a month and want the lowest price: Essentials is $6.99 a month or $69.99 a year
- Your work is quick jobs where an estimate turns into one invoice and nothing changes in between
- You want card, ACH, buy now pay later and Tap to Pay processed in the same app
- You want customizable estimate and invoice templates and unlimited estimates on every paid plan
- You want invoice due date reminders, photos and summary reports from Plus at $14.99 a month
- You want a Bookkeeping add-on with bank transaction import and profit and loss reports from the same vendor
Before you compare them
- Both make estimates and invoices, take a signature and handle partial payments. The difference is what sits around those documents.
- Invoice Simple's strongest documented advantages are its $6.99 entry price, payment processing with cards, ACH, buy now pay later and Tap to Pay, and customizable templates with unlimited estimates on paid plans.
- Clamp's advantage is the job record around the documents: an estimate at cost with markup applied once, a signed proposal whose milestones become the payment schedule, change orders, customer decisions, receipts, time, mileage and the estimate-against-actual job cost review.
- Invoice Simple limits invoices by plan: 3 a month on Essentials, 10 on Plus, unlimited on Premium. Clamp has unlimited documents on every plan.
- Invoice Simple's help page says its client signature is for presentation and is not a legally binding contract.
- Invoice Simple processes payments and charges a fee on each one. Clamp records payments made through your own payment link and does not process payments.
- Invoice Simple publishes no per-plan user count. Clamp Teams covers up to 10 accounts plus free sub invites.
- "Not found" on this page means not found on Invoice Simple's current pricing, features, official information, fee schedule or help center pages. It does not mean Invoice Simple cannot do it another way.
- Neither product was tested against the other. No speed or accuracy claim is made.
Workflow
| Feature | Clamp | Invoice Simple |
|---|---|---|
| Price to start | Solo $19.99 a month or $149.99 a year, free for the first month on monthly billing | Essentials $6.99 a month or $69.99 a year; Plus $14.99 or $149.99; Premium $21.99 or $219.99 |
| Invoices per month | Unlimited documents on every plan | 3 on Essentials, 10 on Plus, unlimited on Premium |
| Estimates | Line by line at direct cost, with your markup applied once and allowances visible | Unlimited on paid plans, on customizable templates, converting to invoices |
| Proposal and contract | A proposal carrying the milestones, signed in the customer portal (Assistant and Teams); a design agreement document on every plan | A design agreement or proposal document was not found on Invoice Simple's official pages |
| Client signature | Proposals and change orders e-signed in the customer portal (Assistant and Teams) | Client estimate signatures on Premium; Invoice Simple's help page says they are for presentation, not a legally binding contract. Owner signature from Plus |
| Change orders | Every plan: priced and billed, e-signed in the portal on Assistant and Teams, with the new contract total shown before signing | Not found on Invoice Simple's official pages |
| Deposits and payment schedules | Every plan: milestones tied to job events, billed as each stage starts; the deposit is the first milestone | Deposits on Premium; multiple scheduled payments by amount or percentage with Stripe, lowest plan not stated |
| Payments | Not processed by Clamp: add your own payment link and record what was paid; no processing fee | Processed in the app: card up to 3.49% + $0.49, ACH 1% + $0.30 capped at $15, buy now pay later 4.99% + $0.49, Tap to Pay 2.79% + $0.49, instant payouts 1.50% |
| Reminders | Email reminders on Assistant and Teams | Invoice due date reminders from Plus |
| Customer portal | One place to sign proposals and change orders, see milestones, invoices, photos and schedule, and answer decisions (Assistant and Teams) | Not found on Invoice Simple's official pages; customers receive emailed documents |
| Receipts and expenses | Receipts and vendor bills recorded against the job | Scanned or manual expenses with receipt images; lowest plan not stated |
| Job costing | Every plan: receipts, vendor bills, time at the loaded rate and labor, reviewed against the estimate at close | Not found on Invoice Simple's official pages; expense summaries and the Bookkeeping add-on's business reports are not compared against an estimate |
| Business mileage log | Automatic trip detection, confirmed per trip, at the IRS rate for its date | Not found on Invoice Simple's official pages |
| Time on site | Logged by role, or detected automatically when you leave a job site; not a GPS crew time clock with geofencing | Not found on Invoice Simple's official pages |
| Team and subs | Up to 10 accounts on Teams, plus unlimited free sub invites who never see your prices | No per-plan user count published; support can add another email to an account after verifying ownership |
| Accounting and export | Not accounting software: an accountant export package, no ledger, payroll, bank feeds or tax filing | Invoice and expense summaries as PDF, XLSX or CSV; a paid Bookkeeping add-on with bank import, profit and loss and balance sheet, price not published |
What was and was not tested
What was compared: Hands-on testing of either product. Neither was tested against the other, and no speed or accuracy claim is made. Documented, not tested.
| Statement | Basis |
|---|---|
| Published by Clamp, using each product's own pricing, feature, fee schedule and help pages. | Clamp's own statement |
| Up to 3 invoices a month, one person, billed annually: Invoice Simple Essentials is $69.99 a year and Clamp Solo is $149.99, so Invoice Simple costs $80 a year less, calculated. | Calculated from published prices |
| 4 to 10 invoices a month, billed annually: Invoice Simple Plus and Clamp Solo are both $149.99 a year. Past 10 invoices a month, Invoice Simple Premium is $219.99 a year and Clamp Solo stays at $149.99. The plans are not equivalent: Invoice Simple includes payment processing, and Clamp includes change orders, job costing and mileage. | Calculated from published prices |
| Invoice Simple's client signature, on Premium, is for presentation and is not a legally binding contract, according to its own help page. | Verified against a published source |
| A crew price could not be calculated for Invoice Simple because it publishes no user count. Clamp Teams is $999.99 a year for up to 10 accounts. | Calculated from published prices |
Switching
- Export your invoice and expense summaries from Invoice Simple as PDF, XLSX or CSV, and save your expense photos, before you cancel.
- Do not assume Invoice Simple history can be imported into Clamp; confirm formats first.
- If you take cards, ACH or Tap to Pay through Invoice Simple, set up your own payment link before you switch; Clamp does not process payments.
- Finish open jobs and any scheduled payments where they started; start new jobs in Clamp.
- If you use the Bookkeeping add-on, decide where your bookkeeping will live; Clamp is not accounting software.
Questions
How much is Invoice Simple, and how many invoices does each plan allow?
Essentials is $6.99 a month or $69.99 a year and allows 3 invoices a month. Plus is $14.99 or $149.99 and allows 10. Premium is $21.99 or $219.99 with unlimited invoices. Estimates are unlimited on every paid plan. Clamp Solo is $19.99 a month or $149.99 a year, with unlimited documents on every plan.
Is Invoice Simple's client signature legally binding?
No, by Invoice Simple's own account. Client signatures on estimates come with Premium, and its help page says the signature is for presentation and is not a legally binding contract. Owner signatures start on Plus. In Clamp, customers sign proposals and change orders in the customer portal on Assistant and Teams.
Does Invoice Simple handle change orders or job costing?
Neither was found on Invoice Simple's official pages. It records scanned or manual expenses with receipt images and exports invoice and expense summaries as PDF, XLSX or CSV, and a paid Bookkeeping add-on gives profit and loss and balance sheet reports. None of that compares a job's actual cost with its estimate. Clamp has change orders and job costing on every plan.
What does Invoice Simple charge to take payments?
On its US standard schedule, card payments are up to 3.49% plus $0.49, ACH is 1% plus $0.30 capped at $15, buy now pay later is 4.99% plus $0.49, and Tap to Pay is 2.79% plus $0.49. Accepting deposits is on Premium. Clamp does not process payments; you add your own payment link and record what was paid, so Clamp charges no processing fee.
Can a crew share an Invoice Simple account?
Invoice Simple publishes no user count for any plan. Its help center says support can add another email to an account after verifying ownership, which does not establish separate seats or role permissions. Clamp Teams covers up to 10 accounts for $999.99 a year or $99.99 a month, and subcontractor invites are free.
Is there a free version of Invoice Simple?
Invoice Simple documents 2 free invoices on the web and a 14-day Premium trial in the mobile app. An ongoing free plan with a monthly invoice allowance was not found on its official pages. Clamp's estimate generator is free, and Solo is free for the first month on monthly billing.
Sources & provenance
- Pricing plans and packages Invoice Simple (official source)
- Premium pricing and full plan comparison Invoice Simple (official source)
- Official information about Invoice Simple Invoice Simple (official source)
- Payments fee schedule Invoice Simple (official source)
- How do I schedule a payment? Invoice Simple (official source)
- Is the client signature legally binding? Invoice Simple (official source)
- How do I keep a record of expenses? Invoice Simple (official source)
- Export invoice or expense summaries Invoice Simple (official source)
- Give someone else access to an account Invoice Simple (official source)
- Set taxes on invoices and estimates Invoice Simple (official source)
- Invoice Simple features Invoice Simple (official source)
- Set up Bookkeeping with Invoice Simple Invoice Simple (official source)
- Financial reports with Bookkeeping Invoice Simple (official source)
- Clamp Pricing Clamp Research
- The Clamp Method Clamp Research
Changes: Oct 15, 2026: Initial publication.