Invoice INV-0142, ₹85,000, due 30 Oct, long-time client
You get
Due date: 'Hi Priya, a quick note that INV-0142 (₹85,000) is due today. UPI and bank details below…'
7 days late: 'Could you check where INV-0142 is in your payment run?'
Final: 'If it's not received by 25 Nov, we'll need to pause work.'
About this skill
About Payment reminder writer
Overdue invoices stay unpaid partly because reminders are awkward to write. This skill writes a sequence that moves from polite to firm: a note before the due date, one on the day, then at seven and twenty-one days late, and a final notice, plus a phone script. Each includes payment details and an easy way to pay. Late fees are only mentioned if your contract has them, and it never threatens legal action you haven't decided to take. To use it, paste the skill into your assistant and send the invoice number, amount, due date, client and your relationship; the reply opens with “Five reminders with subject lines”.
Payment reminder writer — example input and the first lines it returns. Works in ChatGPT, Claude and Gemini.
2 Paste it into a new chatChatGPT, Claude, Gemini or Copilot.
3 Send your inputSend the invoice number.
The skill — paste this into your AI assistant
# Skill: Payment reminder writer
You are running the "Payment reminder writer" skill for me. I work as: Accounts receivable / freelancer. What I need from you: a polite-to-firm sequence of payment reminders for each stage of lateness.
## When I send you the invoice number, amount, due date, client and my relationship
1. Write reminders for: 3 days before due, due date, 7 days late, 21 days late, final notice.
2. Escalate tone gradually while staying professional.
3. Include payment details and an easy way to pay.
4. Mention late fees only if your contract has them.
## Reply in this format
- Five reminders with subject lines
- Phone script for the 21-day stage
## Rules
- Never threaten legal action unless the user says they will take it.
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.
Confirm you're ready in one line, then wait for me to send the invoice number, amount, due date, client and my relationship.
Then sendThe invoice number, amount, due date, client and your relationship. For example: Invoice INV-0142, ₹85,000, due 30 Oct, long-time client
ChatGPT
Fastest: paste the skill as your first message in a new chat, then send your input.
To keep it: open a Project, choose Instructions (or Settings → Personalization → Custom instructions for every chat) and paste it there.
To share it with a team: create a custom GPT and paste the skill into its Instructions.
In the Codex app: copy the skill's folder into ~/.codex/skills/ (or Customize → Skills → Add → Create skill).
Claude
Fastest: paste the skill as your first message in a new chat, then send your input.
To keep it: create a Project, open Project instructions and paste the skill.
As a Claude Skill: download the skill's ZIP, then in Claude open Settings → Skills → Add → Upload skill and choose the file.
Gemini
Fastest: paste the skill as your first message in a new chat, then send your input.
To keep it: open Gems → New Gem, paste the skill into Instructions and save.
Microsoft Copilot
Fastest: paste the skill as your first message, then send your input.
In Microsoft 365 Copilot, save it as a prompt or paste it into an agent's instructions to reuse it.
Any other assistant
Paste the skill as the system prompt or first message in any chat assistant (Perplexity, Meta AI, DeepSeek, Mistral, local models).
Coding agents that read the Agent Skills format (SKILL.md) can load the downloaded file from their skills folder.
Install it permanently
Upload it to Claude, add it to ChatGPT's Codex app, clone it into Claude Code, or download the SKILL.md for any agent. Full guide with screenshots →
Download the ZIP and upload it in Claude. Claude then uses the skill on its own whenever a request matches.
Claude Code: save it as ~/.claude/skills/accounts-receivable-chaser/SKILL.md.
Claude apps: use the Claude app tab — it has a ready-made ZIP.
Other agents: place the folder wherever your tool loads Agent Skills from.
Repositoryscienceofapps.com/skills/ai-skills.git · all 200 skills, one folder each, plain git over HTTPS
What it does
The steps it follows
Write reminders for: 3 days before due, due date, 7 days late, 21 days late, final notice.
Escalate tone gradually while staying professional.
Include payment details and an easy way to pay.
Mention late fees only if your contract has them.
What you get back
The reply format
Five reminders with subject lines
Phone script for the 21-day stage
Rules it never breaks
Never threaten legal action unless the user says they will take it.
Uses only the facts you give it and marks assumptions.
FAQs
Questions about Payment reminder writer
What does the Payment reminder writer skill do?
Overdue invoices stay unpaid because reminders are awkward to write. The skill fixes that: a polite-to-firm sequence of payment reminders for each stage of lateness.
How do I install Payment reminder writer in ChatGPT, Claude or Gemini?
Copy the skill and paste it as the first message of a new chat, then send your input. To keep it, paste it into a ChatGPT Project or custom GPT, a Claude Project or a Gemini Gem, or upload the SKILL.md file as a Claude Skill.
What do I send Payment reminder writer after installing it?
Send the invoice number, amount, due date, client and your relationship. If something essential is missing, the skill asks you one short question and then continues.
Is the Payment reminder writer skill free?
Yes. It's free to copy, use and adapt, with no sign-up, and works in the free versions of ChatGPT, Claude, Gemini and Copilot.
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