Invoice reminders that get you paid, without the awkward follow-ups

The payment reminder app for freelancers. Nüdge Theory sends polite, professional reminders automatically, so you focus on your work, not chasing invoices.

No invoicing software needed.

30-day money-back guarantee. No questions asked.

Nüdge Theory is invoice reminder software built for freelancers. Set up a reminder in under a minute. Polite, automatic follow-ups handle the rest. Works with any invoicing tool you already use.

Why we built this

The email you never have to write

There is a moment every freelancer knows. The work is done. The invoice is sent. And then the waiting begins. Not for the money. For the courage to ask for it.

We built Nüdge Theory because that moment should not exist. A well-timed, gentle reminder changes behavior more reliably than pressure, ultimatums, or silence. Not because people are weak. Because people are busy.

Your client gets a polite heads-up. The invoice gets paid. The relationship stays intact. You never had to write the awkward email.

Read our story →

The problem

Chasing payments is uncomfortable

You did the work. You sent the invoice. Now you're waiting, wondering if you should send a reminder without sounding pushy.

"Hey, just checking in on invoice #247... no rush, but wanted to make sure it didn't get lost..."

1,386

Reminders sent

How it works

How automated invoice reminders work

1

Create a reminder

Add your client's email, invoice amount, and due date. Takes less than a minute.

2

Nüdge Theory sends reminders

Polite, professional emails go out before and after the due date, automatically.

3

You get paid

Clients pay on time. You never had to send an awkward follow-up.

Why Nüdge Theory

Why freelancers choose payment reminder software

Because you have better things to do than chase invoices.

Save hours every month

Stop tracking due dates and drafting reminder emails. Nüdge Theory does it for you, on schedule, every time.

Keep relationships healthy

Our reminders are friendly and professional. Clients appreciate the heads-up, not the pressure.

Look more professional

Consistent, well-timed reminders show clients you run a real business, even if it's just you.

Pays for itself instantly

One late payment recovered more than covers the cost. Most freelancers save hundreds per year.

See it in action

Payment reminders that sound human

Our reminders are warm and polite, the kind of email you'd write yourself if you had the time. No robotic templates. No aggressive language.

Customizable tone and timing
From:you@yourname.com
To:client@company.com
Subject:Quick reminder: Invoice #1042

Hi Sarah,

Hope you're doing well! Just a friendly reminder that invoice #1042 for $2,400 is due this Friday, March 15th.

No rush if it's already in process, just wanted to make sure it didn't slip through the cracks.

Thanks so much,
Alex

Pricing

Simple, transparent pricing

Choose the plan that fits your needs.

Solo

$29/mo USD

Everything you need to get paid on time. Period.

  • Up to 10 active clients
  • 100 active reminders
  • 450 email reminders per month
  • Automated pre-due and overdue reminders
  • Attach invoices (PDF, PNG, XLSX) to emails
  • Recurring reminders for retainer clients
  • Pick your tone: friendly, professional, or direct
  • Morning digest: daily payment status summary
  • Autosave drafts so you never lose progress
  • One-click mark as paid from your inbox
  • Custom reminder schedules
  • 5 saved email templates
  • 5 file attachments per reminder, 4 MB each
Most popular

Growth

$59/mo USD

For freelancers turning their side hustle into a real business.

  • Everything in Solo, plus:
  • Up to 30 active clients
  • 500 active reminders
  • 1,500 email reminders per month
  • Payment pattern insights: see who pays late
  • 20 saved email templates
  • Priority support

Studio

$109/mo USD

For studios and small agencies managing multiple client relationships.

  • Everything in Growth, plus:
  • Unlimited active clients
  • 1,000 active reminders
  • 3,000 email reminders per month
  • Bulk actions: mark paid, cancel, manage at scale
  • CSV export for accounting and reporting
  • Priority email queue: your reminders send first
  • Unlimited saved templates
  • Dedicated support

Included in every plan

Invoice attachments|Recurring reminders|4 reminder tones|Morning digest|Autosave drafts|One-click mark as paid|Custom schedules

30-day money-back guarantee. No risk, no hassle.

Questions

Common questions

Does this replace my invoicing software?

No, Nüdge Theory only handles reminders. You keep using whatever tool you already use to create and send invoices (FreshBooks, Wave, even a simple PDF). Nüdge Theory just makes sure clients don't forget to pay. Learn more in our guide to payment terms.

Will clients know it's automated?

All plans include a small "Sent automatically by Nüdge Theory" note at the bottom of reminder emails for transparency. Clients see professional, personalized reminders that feel like they came directly from you.

Can I stop reminders anytime?

Absolutely. Mark a reminder as paid with one click and all scheduled emails stop immediately. You're always in control.

What if my client pays before the reminder goes out?

Just mark the invoice as paid in your dashboard. Nüdge Theory won't send any more reminders for that invoice. It takes two seconds.

How do I remind clients to pay without being pushy?

Nüdge Theory sends automated invoice reminders on a schedule you control: before the due date, on the due date, and after. Each reminder uses professional, friendly language so you never have to write an awkward follow-up email again.

What if I'm not satisfied?

We offer a 30-day money-back guarantee. If Nüdge Theory isn't working for you, email us at hello@nudgetheory.app within 30 days of your first payment and we'll refund you in full, no questions asked.

Ready to stop chasing payments?

Set up your first reminder in under a minute.