Why Phone-Based Invoicing is a Game Changer for Contractors
For decades contractors had two choices: drive back to the office to print an invoice, or send a handwritten one that looked unprofessional. Neither was good.
Mobile invoicing changes everything. With the right app you can:
- Send a professional invoice the moment a job is finished
- Include all your payment options automatically
- Give the customer a tap-to-view link they can reference anytime
- Follow up on unpaid invoices with one tap
- Track every job and customer from your pocket
Invoices sent within 24 hours of job completion are paid 3x faster than invoices sent later. Mobile invoicing makes same-day invoicing effortless.
What You Need to Invoice from Your Phone
To send professional invoices from your phone you need just three things:
- A smartphone — iPhone or Android, any model from the last 5 years works fine
- A mobile invoicing app — We recommend FieldPay (more on that below)
- Your customer's phone number or email — That's it
You don't need a laptop, printer, accounting software, or any special equipment. Everything runs on your phone.
How to Send an Invoice from Your Phone: Step by Step
Set up your business profile
Enter your business name, phone number, address, and payment handles (PayPal, CashApp, Venmo). This only takes 2 minutes and never needs to be done again.
Add your customer
Enter the customer's name, phone number, and email. Save them and they'll be in your contacts for future jobs.
Create the invoice
Select the customer, choose the job type, and add your line items. Use saved labor rates to pre-fill common charges. The whole thing takes under 30 seconds once you're set up.
Send via text or email
Tap Send. Your phone's Messages or Mail app opens with the invoice pre-written. Just hit send. The customer receives a professional invoice link instantly.
Get paid
The customer taps the link, sees your invoice with all payment options, and pays you via their preferred method. Mark it paid in the app when the money comes in.
Choosing the Right Mobile Invoicing App
Not all invoicing apps are truly mobile first. Many are desktop apps with a mobile version tacked on. Here's what to look for:
Works without an app store download
The best mobile invoicing apps run in your phone's browser — no app store download needed. This means you can get started in seconds and never worry about updates.
Designed for one-handed use
You're standing in a customer's driveway. You need to be able to create and send an invoice with one thumb. The app should be simple enough to use without reading a manual.
Supports your payment methods
Most contractors collect payment via cash, check, Venmo, CashApp, or PayPal. Your app should show all of these on every invoice automatically — not just credit card processing.
Works offline or with poor signal
Job sites often have poor cell service. Your app should work even with a weak signal.
How to Invoice for Cash, Venmo, CashApp, and PayPal
One of the biggest advantages of mobile invoicing is being able to collect payment on the spot using apps your customers already have on their phones.
With FieldPay you set up your payment handles once:
- Your PayPal email or @username
- Your CashApp $cashtag
- Your Venmo @username
These appear automatically on every invoice you send. The customer sees exactly where to pay you. No confusion, no back and forth about how to send money.
Offering multiple payment options increases your chance of getting paid immediately. Some customers prefer Venmo, others prefer CashApp. Show them all and let them choose.
How to Handle Sales Tax on Mobile Invoices
Sales tax can be tricky for contractors because the rules vary by state and job type. In most states:
- Materials are taxable — shingles, pipe, lumber, parts
- Labor is not taxable — installation, service calls, cleanup
A good mobile invoicing app handles this with per-line-item tax control. In FieldPay each line item has a T button — tap it to mark the line as taxable or non-taxable. The app calculates the correct tax automatically and shows the breakdown on the invoice.
Always consult your accountant about your specific state's sales tax rules for contractors.
Tips for Getting Paid Faster with Mobile Invoicing
- Invoice immediately after the job. Don't wait until you get home. Send it before you back out of the driveway.
- Include a professional invoice link. A tap-to-view invoice looks more legitimate than a text message with numbers. Customers take it more seriously.
- Offer multiple payment options. The easier you make it to pay the faster they pay.
- Follow up on unpaid invoices. Set a reminder for 3 days and send a polite reminder if you haven't been paid.
- Add notes to invoices. A brief description of the work done reduces disputes and questions.
Adding FieldPay to Your Phone Home Screen
FieldPay works as a Progressive Web App (PWA) — meaning you can add it to your phone's home screen and it opens full screen like a native app, with no app store required.
On iPhone:
- Open fieldpayapp.com in Safari
- Tap the Share button at the bottom of the screen
- Scroll down and tap Add to Home Screen
- Tap Add
On Android:
- Open fieldpayapp.com in Chrome
- Tap the three-dot menu at the top right
- Tap Add to Home Screen
- Tap Add
Once installed it appears on your home screen just like any other app. Opens instantly with no browser bars.
Ready to start invoicing from your phone?
Start sending invoices from your phone today — free for 14 days.
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