GST invoice with AI: make invoices and payment reminders

Yes. AI can draft GST tax invoices with the right CGST, SGST or IGST, share a UPI payment link and email payment reminders. Here is how to set it up.

By the KutrimBots teamPublished November 6, 202610 min read

Yes. An AI agent can make your GST invoices for you: you say "bill Mehta Traders ₹50,000 for October's social media work", and it drafts a numbered tax invoice on your letterhead with the right HSN or SAC code and CGST plus SGST or IGST, then waits for your OK before issuing it. Once issued, it can share a pay-by-UPI link and email polite payment reminders before and after the due date, so you stop rebuilding invoices in Excel and chasing clients one message at a time.

This tutorial covers what a GST invoice must contain, how to set up AI invoicing in KutrimBots step by step, how the reminders work, and what still needs you and your CA.

Why do clients pay late, and why does Excel make it worse?

Most late payments are not refusals; they are invoices nobody followed up on time. Small suppliers carry the cost. As of August 14, 2026, micro and small enterprises had filed 2,56,892 delayed-payment cases worth ₹55,244 crore on MSME Samadhaan, with ₹20,979 crore still pending, according to Crisil's analysis of the portal data. The law is on your side if you are a registered micro or small supplier: under Sections 15 and 16 of the MSMED Act, 2006, a buyer must pay within the agreed period, which cannot exceed 45 days, or owe compound interest at three times the RBI bank rate.

A spreadsheet doesn't help with any of that. It doesn't know which invoice is overdue, it can't email anyone, and copying last month's sheet is how duplicate invoice numbers and wrong tax splits happen.

What must a GST tax invoice contain?

A tax invoice must carry the particulars listed in Rule 46 of the CGST Rules. The main ones, as of November 2026:

Particular	What it means in practice
Your details	Name, address and GSTIN
Invoice number	Consecutive, at most 16 characters, letters, numbers, "-" and "/" only, unique for the financial year
Date of issue	The date you issue it
Customer's details	Name, address and GSTIN if registered; for unregistered customers, name, address and state when the taxable value is ₹50,000 or more
HSN or SAC code	HSN for goods, SAC for services
Description, quantity, unit	What you sold and how much
Total and taxable value	After any discount
Tax rate and amount	CGST and SGST, or IGST, shown separately
Place of supply	With the state name, for inter-state supplies
Reverse charge	Whether tax is payable on reverse charge
Signature	Yours or your authorised representative's, physical or digital

Three more rules matter:

Rates changed in 2025. Since September 22, 2025 most goods and services sit in two slabs, 5% and 18%, with a 40% rate for a short list of sin and luxury items, as the GST Council's 56th meeting recommended. Many old invoice templates still carry 12% and 28%.
E-invoicing above ₹5 crore. If your aggregate turnover in any financial year since 2017-18 crossed ₹5 crore, your B2B invoices must be registered on the Invoice Registration Portal to get an IRN and QR code, under Notification 10/2023-Central Tax, in force since August 1, 2023.
30-day window above ₹10 crore. Businesses with turnover of ₹10 crore or more must report each e-invoice within 30 days of its date, under a GSTN advisory effective April 1, 2025.

Rules change, and your situation (composition scheme, exports, reverse charge) changes the answer. Confirm your setup with your CA once, then let the software apply it every time.

Can AI create an invoice for me?

Yes, if the AI uses a real invoicing system rather than writing a document from scratch. A chat assistant can produce something that looks like an invoice, but it won't keep your numbering, record payments or know what's overdue. In KutrimBots, the agent works inside the Invoices & Billing plugin, which does the tax maths, numbering, letterhead, PDF and records, so the agent's job is to fill in the right details and ask you to approve.

Task	In Excel	With an AI agent in KutrimBots
Tax split	You decide CGST + SGST or IGST each time	Worked out from your GSTIN and the customer's GSTIN or billing state
HSN or SAC code	Looked up manually	The agent checks the tax lookup, or confirms an unusual one with a web search
Invoice number	Typed by hand	Given on issue, unique per financial year (default like `INV/26-27/0001`)
Corrections	Edit the old file	Issued invoices are locked; fixes go through a credit or debit note
Sending	Export PDF, attach, write email	One approval: emailed with the PDF, or shared as a link with a UPI QR code
Who has paid	A colour in a cell	Recorded payments with UTR, statuses, and an overdue list every morning
Reminders	You remember, or don't	Emailed on the schedule you set

How to make your first GST invoice with AI in KutrimBots

These steps take about 20 minutes the first time.

Pick the agent that will do your billing. Invoices & Billing is built in on every plan and given automatically to agents with the Sales, Finance, Assistant or Support role. A finance or assistant agent is a good owner.
Create your business profile. Ask the agent "set up my invoicing". It asks for your business name, address with state, GSTIN, PAN, email, phone, bank account with IFSC, and UPI ID, then saves the profile after your approval. In India the state is read from your GSTIN.
Add your logo and signature. Upload them in Invoices & Billing → Settings, so every PDF goes out on a proper letterhead. You can keep several businesses in one workspace, each with its own profile.
Add the customer. Give the agent the client's name, email and GSTIN. The GSTIN decides the tax: same state means CGST + SGST, another state means IGST. For a customer without a GSTIN, it asks for the billing state. If the client is already a CRM lead, the invoice links to the lead's timeline.
Ask for the invoice in plain words. For example: "Invoice Mehta Traders ₹50,000 plus GST for October social media management, due in 15 days." The agent picks the SAC code and rate from the tax lookup and shows you a draft: ₹50,000 + CGST 9% ₹4,500 + SGST 9% ₹4,500 = ₹59,000.
Check and approve. Change anything with a sentence. When you approve, the invoice gets its number, is locked, and its PDF is saved in File Manager → Invoices.
Send it. Approve an email from your business email login (saved once in the Security Vault), or a public link to the customer page, where the client can download the PDF and pay by UPI from a QR code with the amount filled in.
Record the payment. When money arrives, tell the agent "Mehta paid ₹59,000 by UPI, UTR 4123…". If the client deducted TDS, give the amount and section (194J for professional fees, for example) and the invoice is settled correctly.

Quotes and proformas work the same way: draft a quote, the client accepts it on the customer page, and the agent turns it into an invoice with one instruction. Monthly retainers can repeat on their own once you approve the schedule. If you sell from a CRM, our guide to CRM lead follow-up with AI shows how a lead becomes a quote.

How does AI send payment reminders for invoices?

Reminders go out by email, on a schedule you choose, from your own business email login. You turn them on once in Invoices & Billing → Settings and tick the steps you want:

Reminder step	When it goes out
Before due	3 days before the due date
Due today	On the due date
First overdue	3 days late
Second overdue	7 days late
Final	14 days late

Each reminder is short and polite, with the invoice number, the balance, the due date and a link to the customer page to pay by UPI. They are sent every morning at about 9:30 for unpaid invoices that have a customer email, and they stop when the invoice is paid. Every morning the plugin also marks late invoices as overdue and tells you what's owed.

Three extras are worth knowing:

Late fees. You can set a flat fee (say ₹500) or a percentage of the balance after a number of grace days. The plugin drafts the fee as a debit note for you to review and issue; nothing is charged on its own.
A personal follow-up. For big invoices, an automation can hand an overdue invoice to your finance agent, which drafts a personal email referring to the work done, and waits for your approval before sending. Our guide to the AI email assistant explains how agents handle email.
WhatsApp. The reminders themselves are emails. If your clients live on WhatsApp, copy the customer page link into your chat with them; the page shows the balance due and lets them pay with a UPI app or scan the QR code on the invoice.

Example scenario

A four-person digital marketing agency in Pune bills 18 retainer clients a month, averaging ₹45,000 plus 18% GST. Twelve clients are in Maharashtra and six are in other states.

Before: the owner spends about 15 minutes per invoice in Excel (copying last month's sheet, fixing the tax split, exporting a PDF, sending it on WhatsApp), about 4.5 hours a month, plus Friday afternoons scrolling chats to see who hasn't paid. Two invoices a month usually slip past 30 days.
After: the 12 in-state invoices show CGST + SGST and the 6 out-of-state ones show IGST automatically. Retainers repeat on the 1st as drafts; the owner reviews 18 drafts in about 20 minutes and approves them. Reminders go 3 days before the due date and again at 3, 7 and 14 days late.
On day 7 of an overdue ₹53,100 invoice, the agent drafts a personal note to the client's accounts team. The owner approves it from her phone, then forwards the customer page link to the client's WhatsApp herself.
At month end, she exports the register to Excel for her CA: one row per invoice with taxable value, CGST, SGST, IGST, paid and balance.

These numbers are illustrative; your time saved depends on how many invoices you raise and how they're paid.

What it can't do

Being clear about the limits saves you trouble later:

It doesn't file GST returns. The register export and the tax-by-rate report help your CA prepare GSTR-1 and GSTR-3B, but filing stays with you or your CA.
It doesn't generate e-invoices (IRN). If you are above the ₹5 crore threshold, generate the IRN on the Invoice Registration Portal and give it to the agent; it prints on the invoice.
It doesn't send reminders on WhatsApp or SMS. Automatic reminders are emails; the link is yours to share in chats.
It doesn't confirm UPI payments by itself. You or the agent record each payment with its UTR.
It doesn't decide tax questions. The built-in rates are as of October 2026, a line's own rate always wins, and unusual items are checked with a web search. Confirm anything unusual with your CA.

Approvals are built in: saving your business profile, issuing, voiding, emailing and sharing an invoice all wait for your OK. For more on how approvals keep agents in check, read are AI agents safe.

How to try it

KutrimBots is a team of always-on AI agents with invoicing, CRM, inboxes and more built in. You can start the free 7-day trial on the Solo plan: add a card or UPI, nothing is charged today, and it becomes $20 a month after seven days unless you cancel in Plan & billing. Make one real invoice during the trial and check it with your CA before you switch over fully.

Frequently asked questions

Can AI make a GST invoice for free?

Free AI chat tools can format an invoice, but they don't keep numbering, record payments or send reminders. KutrimBots includes Invoices & Billing on every plan, from $20 a month, with a free 7-day trial.

Is an invoice made with AI valid for GST?

Validity depends on the contents, not on who typed it. If the invoice carries the Rule 46 particulars (your GSTIN, a unique number, the customer's details, HSN or SAC, taxable value, tax rate and amount, place of supply and signature), it's a valid tax invoice. Confirm your format with your CA once.

Can it generate e-invoices with an IRN?

No. If your turnover requires e-invoicing, generate the IRN on the Invoice Registration Portal and add it to the invoice in KutrimBots, where it prints on the PDF.

Can the AI send payment reminders on WhatsApp?

Automatic payment reminders are sent by email. You can paste the customer page link, which shows the balance due and a pay-by-UPI option, into WhatsApp yourself.

Can I add my logo, letterhead and UPI details to the invoice?

Yes. Your business profile holds your address, GSTIN, PAN, bank details and UPI ID, and you upload your logo and signature in Invoices & Billing → Settings. Every PDF uses that letterhead.