How to Add a Customer in Nastrum Books - Complete Setup Guide (2026)

Your customer list is the foundation of your entire sales operation. Every invoice, estimate, payment, and statement traces back to a customer record. Setting it up properly from the start — with the right payment terms, currency, contacts, and documents — saves you time every single time you do business with that client.

This guide walks through the complete customer setup process in Nastrum Books, from the 5-step creation wizard to reading a live account statement. Every field is explained so you know exactly what to enter and why it matters.

New to Nastrum Books? Start with setting up your company first.

Every step from the video is written out below with additional detail.

The Customers Module — What It Does

Navigate to Customers in the left sidebar under Sales.

The customers list shows every client in your database with:

• Name and avatar
• Company name
• Email address
• Phone number
• Status (Active / Inactive)
• Revenue — total amount invoiced and paid
• Balance — outstanding amount currently owed

You can search by name, email, company, or phone number. Filter by status or tags. Export the full list to CSV or import customers in bulk.

Each customer entry has a three-dot menu for quick actions: view, edit, or delete.

The 5-Step Customer Wizard

Clicking + New Customer opens a clean 5-step wizard. The tabs at the top show your progress: Basic Info → Addresses → Contacts → Financial → Additional.

You can navigate between tabs freely — nothing is saved until you click Save at the end.

Step 1: Basic Info

Customer Type

The first choice is customer type: Business or Individual.

Business — for companies, agencies, or any organisation. Shows:

• Business Name (required)
• Display Name
• Email (required)
• Phone
• Website
• Company

Individual — for sole traders, freelancers, or private clients. Shows:

• First Name + Last Name
• Full Name (required)
• Display Name
• Email (required)
• Phone
• Website
• Company

Switching between types updates the form instantly — no page reload.

Business Name vs Display Name

The Business Name is the official legal name used internally and on reports. The Display Name is what appears on invoices, estimates, and statements sent to the customer. It defaults to the business name but you can customise it — useful if you want invoices to show “Costner” instead of the full “Costner LLC”.

Email

Required. This is the primary address where invoices, estimates, and statements will be delivered when you use Nastrum Books email delivery. Make sure it is the accounts payable address, not a personal mailbox that might be checked infrequently.

Example values used in this tutorial:

• Business Name: Costner LLC
• Display Name: Costner LLC
• Email: info@costner.com
• Website: www.costner.com
• Company: Costner LLC

Click Continue to move to step 2.

Step 2: Addresses

This step captures three address types:

Primary Address

The main registered or office address. Fields:

• Street
• City
• State / Province
• ZIP / Postal code
• Country (dropdown — 200+ countries)

Billing Address

The address that appears on invoices. Tick Same as primary to auto-fill. If your customer has a separate accounts department at a different location, untick and enter it manually.

Shipping Address

The delivery address for goods. Tick Shipping same as billing to auto-fill. For service businesses this is usually not needed, but it is available for those who ship physical products.

The address you enter here flows automatically into the customer address block on every invoice and estimate, so you only need to enter it once.

Click Continue to move to step 3.

Step 3: Contacts

This step is often overlooked but is one of the most useful features for B2B businesses.

Additional contacts are the specific people at the customer’s organisation you deal with — not just the main company email. A typical setup for a larger client might include:

• Accounts Manager — for invoice delivery and payment queries
• Project Manager — for day-to-day work communication
• Finance Director — for statement requests and credit decisions

Each contact has four fields:

• Name — the person’s full name
• Role — their job title or function
• Email — their direct email address
• Phone — their direct number

Click + Add Contact to add as many contacts as needed. There is no limit.

Example: Jonas, Accounts Manager, jonas@costner.com, +642 11223344

These contacts are stored on the customer record and visible to your whole team. When sending emails from Nastrum Books, you can select which contact to address.

Click Continue to move to step 4.

Step 4: Financial

This is the most important tab for accounting accuracy. Every field here affects how invoices are generated and how the customer’s account is managed.

Currency

Select the currency for this customer. All invoices created for this customer will default to this currency. If you invoice Costner LLC in NZD, set it to NZD. If you have a US client you invoice in USD, set it to USD.

Nastrum Books supports multi-currency out of the box. If your base currency is AED and you invoice a client in USD, the system handles the conversion automatically using live exchange rates.

Payment Terms (days)

The number of days the customer has to pay from the invoice date. Common values:

When you create an invoice for this customer, the due date is automatically calculated based on these terms. No manual date calculation needed.

Example: 30 days means an invoice raised on 1 March is due on 31 March.

Credit Limit

The maximum outstanding balance you are willing to extend to this customer. If the total unpaid invoices for this customer exceed this limit, Nastrum Books will warn you before you create a new invoice.

This is a risk management tool — particularly useful for businesses that extend credit to customers before receiving payment.

Example: NZ$1,000 credit limit means you will be warned if Costner LLC owes more than NZ$1,000 at any one time.

Set it to 0 if you do not want a limit.

Tax / VAT Number

The customer’s tax registration number. This is required for:

• B2B invoices in VAT-registered countries (UAE, UK, EU)
• GST-registered businesses in India, Australia, New Zealand
• Any jurisdiction that requires tax numbers on invoices

The tax number appears on invoices automatically once set here. You do not need to enter it manually on each invoice.

Click Continue to move to step 5.

Step 5: Additional

The final step captures supplementary information.

Tags

Tags are labels you apply to customers for grouping and filtering. You can create any tag you want — examples:

• Repeat — returning customers
• VIP — high-value accounts
• Wholesale — wholesale buyers
• Retail — retail customers
• UAE / India / UK — by geography
• Q1-2026 — acquired in a specific period

Tags appear on the customer list and can be used as filters. Useful when you have hundreds of customers and need to segment them for reporting or outreach.

Notes

Internal notes visible only to your team — never printed on invoices or statements. Use this for:

• How you met the customer
• Special billing instructions (“Always send invoice to accounts@costner.com CC Jonas”)
• Credit history or risk notes
• Relationship context for new team members

Attachments

Store documents directly on the customer record. Supported formats: PDF, JPG, PNG, Word, Excel — up to 10MB per file, up to 5 files.

Common documents to store here:

• Trade licence — legal requirement in many GCC countries
• Business registration certificate
• Signed credit application
• Master Service Agreement (MSA)
• Non-Disclosure Agreement (NDA)
• KYC documents — Know Your Customer compliance

Having these on the customer record means your whole team has access without hunting through email threads or shared drives.

Example: Trade License Costner LLC.pdf — uploaded at 5KB, dated 31/03/2026.

Status

Set the customer as Active or Inactive.

• Active — appears in all dropdowns, can be invoiced
• Inactive — hidden from dropdowns, cannot be invoiced, but all historical records are preserved

Use Inactive for customers you are no longer working with — it keeps your active list clean without deleting any history.

Save Options

At the bottom you have two save buttons:

• Save & New — saves this customer and immediately opens a blank form for the next one. Useful when adding multiple customers in one session.
• Save — saves and opens the new customer’s detail page.

The Customer Detail Page

After saving, you land on the customer detail page — your command centre for this client relationship.

KPI Cards (5 metrics)

All five update automatically with every transaction. No manual calculation.

Action Bar

The action bar at the top gives you one-click access to everything you need:

• Edit — modify any customer detail
• Delete — permanently remove (only if no transactions exist)
• Add as Vendor — convert this customer into a vendor too (for suppliers who are also clients)
• Send Email — compose and send an email directly from the app
• Statement — generate an account statement PDF
• New Invoice — create an invoice for this customer immediately

Customer Tabs — Deep Dive

Overview Tab

Shows the full contact card: type, email, phone, company, website, address, and financial details (currency, payment terms, credit limit, tax number, tags). Everything you entered in the wizard in one clean view.

Invoices Tab

A complete invoice register for this customer. Filterable by:

• All — every invoice
• Paid — settled invoices
• Pending — sent but not yet paid
• Overdue — past due date
• Draft — not yet sent

Each row shows invoice number, date, status badge, total, amount due, and whether it is overdue.

Click any invoice number to open it directly. No need to navigate to the Invoices section separately.

Live example: Costner LLC has 3 invoices:

• INV-0006 — sent — NZ$289.80 due
• INV-0005 — paid — NZ$0.00 due
• INV-0004 — paid — NZ$0.00 due

Payments Tab

Every payment received from this customer. Includes:

• Date
• Invoice reference (clickable)
• Payment method
• Reference number
• Amount
• Receipt link (download the payment receipt PDF)

Payment behaviour KPIs at the top of the tab:

These KPIs let you assess credit risk and payment reliability at a glance. A customer with “30 days early” and “100% on-time rate” is a safe credit extension. A customer with “45 days late” and “60% on-time rate” warrants caution.

Live example: Costner LLC — 2 payments, NZ$1,015.74 total received, average 30 days early, 100% on-time rate.

Notes Tab

Internal notes for this customer. Add timestamped notes visible to your team — useful for call logs, meeting summaries, or follow-up reminders.

Attachments Tab

Documents stored against this customer. Upload at any time — drag and drop or click to browse. All files are stored in Cloudflare R2 (secure cloud storage) and accessible to authorised team members only.

Activity Tab

A chronological timeline of every event on this customer record:

• Customer created
• Invoice created
• Invoice sent
• Payment received (with amount and method)
• Notes added
• Customer details edited
• Email sent

Each entry shows the event description, timestamp (relative — “2 minutes ago”), and which team member performed the action.

This is your built-in audit trail. If there is ever a dispute about when an invoice was sent or a payment received, the Activity tab has the answer — with no ability to edit or delete the log.

Live example activity:

• Invoice status changed to “sent”
• Invoice INV-0006 created
• Payment received on INV-0004 — NZ$704.38 via Bank Transfer
• Payment received on INV-0005 — NZ$111.36 via Bank Transfer
• Payment received on INV-0005 — NZ$200.00 via Bank Transfer
• Invoice INV-0005 created

Account Statements

Click the Statement button in the action bar to generate a professional Account Statement for this customer.

The statement opens as an overlay with:

Summary Row

• Charges — total amount invoiced
• Payments Received — total amount paid
• Outstanding Balance — what is still owed (highlighted in blue)

Transaction Table

Each row shows:

• Date
• Description (Invoice issued / Payment received)
• Reference (invoice number, clickable)
• Charges column
• Payments Received column
• Running Balance

Footer

Your company bank details — bank name, account number, SWIFT code — automatically pulled from your company settings. This means the customer has everything they need to make a payment at the bottom of the statement.

Date Range Filter

Filter the statement to show: Last month, Last 3 months, Last 6 months, This year, or a custom date range.

Delivery Options

• Download PDF — save to your computer
• Send Statement — email directly to the customer from Nastrum Books (uses your configured email delivery)

Live example: Costner LLC statement shows NZ$1,305.54 charged, NZ$1,015.74 received, NZ$289.80 outstanding — with full line-by-line transaction history.

Customer Management Best Practices

Set payment terms at the customer level, not the invoice level. If you always give Costner LLC 30 days, set it on their record. It auto-applies to every new invoice and you never have to remember.

Use credit limits for new clients. Until you know how reliably a customer pays, set a low credit limit (e.g., NZ$500). Raise it as they build a track record.

Add the tax / VAT number before you invoice. If you forget and send invoices without it, some customers will reject the invoice. Set it once here and it appears on every document automatically.

Tag customers consistently. Agree on a tag taxonomy with your team (“VIP”, “Wholesale”, “New”, “Churned”) and apply it consistently. This lets you filter and report on customer segments easily.

Use the Contacts tab for larger clients. When a client has multiple stakeholders, having them all in the Contacts tab means whoever is handling the account always knows who to contact and for what.

Store documents at onboarding. The moment you sign a client, upload their trade licence, signed contract, or KYC documents. Do it once, access it forever.

Send statements monthly to clients with outstanding balances. One click from the Statement button. It serves as a professional reminder without an awkward phone call.

Frequently Asked Questions

Can I import customers in bulk?

Yes. Click Import on the Customers list page. Download the CSV template, fill it with your customer data, and upload it. Useful when migrating from another system.

Can I export my customer list?

Yes. Click Export on the Customers list page to download a CSV of all customers with their key fields.

Can the same contact be both a customer and a vendor?

Yes. Use the Add as Vendor button on the customer detail page. The contact then appears in both your Customers and Vendors lists — useful for suppliers you also sell to.

What happens if I set a customer to Inactive?

They are hidden from all dropdowns (you cannot create new invoices for them), but all their historical invoices, payments, and records remain intact. You can reactivate them at any time.

Can I set different payment terms per invoice?

Yes. The payment terms set on the customer record are defaults only. When creating an individual invoice, you can override the due date. The customer-level setting just saves you from changing it every time.

Can I have multiple contacts receive invoices?

Currently invoices are sent to the primary email address. The Contacts tab stores additional contacts for reference. Email CC functionality for contacts is on the roadmap.

Is there a limit on how many customers I can add?

No. All plans in Nastrum Books support unlimited customers.

Can I merge duplicate customer records?

Not currently via the UI — if you have duplicates, edit one to be correct and delete the other (only possible if the duplicate has no transactions).

Ready to build your customer database? Create your free account and add your first customer today, or sign in if you already have an account.

Once your customers are set up, the next step is creating your first invoice.