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GST invoicing · service businesses · Interior & architecture

Invoicing Software for Interior Designers & Architects

Stage-wise billing on the project value, material and fee kept apart.

For Interior & architecture businesses

Design projects bill in stages — an advance on signing, running bills at concept, drawings and execution, and a final on handover — often over many months. Your professional fee is taxed differently from any material you procure, so the invoice has to keep the two apart and the advances have to be tracked against the project value.

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Flat ₹399/month · Unlimited users · No card required · Cancel anytime

How interior & architecture billing works

Interior and architecture billing is milestone-based: an advance, then running bills as each stage completes, adjusted against the total project value. 399Apps raises each stage as its own GST invoice with a SAC-coded design fee, keeps procured material as separate line items, and tracks client-wise outstanding across the whole project so you always know how much of the fee is still to bill and to collect.

GST & TDS, handled right

Professional design and architecture services sit under SAC 9983 (or 995411 for architecture) at 18% GST. Advances received against a service attract GST at receipt, and corporate or builder clients deduct TDS at 10% under 194J — 399Apps records the advance, the running bills and the TDS section-wise so the project’s tax position stays clean end to end.

The billing problems it solves

Different service, same trap — money earned that never quite gets billed or collected. Here's what 399Apps keeps straight for interior designers & architects:

Advances lost track of

Record the signing advance and adjust it against running bills so nothing is double-billed.

Fee vs material muddled

Keep the taxable design fee and procured material as separate lines on one GST invoice.

Long projects, slow collection

Stage-wise invoices with due dates and AR aging show which milestones are still unpaid.

194J deducted by builders

Corporate and builder clients withhold TDS — 399Apps logs it for a clean 26AS reconcile.

What you get

  • ✓Stage / milestone GST invoices (SAC 9983)
  • ✓Advance receipts adjusted against bills
  • ✓Design fee vs material line separation
  • ✓Project-wise outstanding & AR aging
  • ✓TDS-on-receipts (194J), 26AS-ready
  • ✓Quotes / estimates → invoice conversion

One flat price — the whole team invoices

Most invoicing tools charge per user or per invoice, so growing your practice grows the bill. 399Apps is a flat ₹399/month for your first app and ₹99/month for each additional app — GST invoicing, TDS reconciliation and receivables in one system, unlimited users, cloud or self-hosted. Adding partners, associates or account managers never raises the price.

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FAQ

Invoicing software for interior designers & architects — FAQ

Does 399Apps work for interior designers & architects? +
Yes. 399Apps (Nidhi Books) is built for the way interior designers & architects actually invoice. Interior and architecture billing is milestone-based: an advance, then running bills as each stage completes, adjusted against the total project value. 399Apps raises each stage as its own GST invoice with a SAC-coded design fee, keeps procured material as separate line items, and tracks client-wise outstanding across the whole project so you always know how much of the fee is still to bill and to collect.
How does GST and TDS work for interior & architecture businesses in 399Apps? +
Professional design and architecture services sit under SAC 9983 (or 995411 for architecture) at 18% GST. Advances received against a service attract GST at receipt, and corporate or builder clients deduct TDS at 10% under 194J — 399Apps records the advance, the running bills and the TDS section-wise so the project’s tax position stays clean end to end.
How much does invoicing software cost for a interior & architecture business? +
A flat ₹399/month for your first app and ₹99/month for each additional app or add-on — the same price across India, with no per-user licence and no per-invoice fee. A solo professional and a growing interior & architecture firm pay the same base price.
Can I track who still owes me and follow up on time? +
Yes. Every invoice carries a due date, and AR Aging buckets receivables into current, 1–30, 31–60, 61–90 and 90+ days overdue with per-client outstanding — so you chase the slippers before the money is really late, without a manual ledger.
Can I run it on the cloud or on my own server? +
Both. Run 399Apps fully managed on the 399apps cloud with daily backups and an India data region, or self-host it on your own server for complete data ownership. The same invoicing and GST features work either way.
Try 399Apps

Affordable invoicing software for interior designers & architects — from ₹399/month

GST invoicing, TDS reconciliation and receivables in one system, with unlimited users. Start your free 14-day trial — no card required.

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