Construction guide · Outlook steps checked 27 October 2026

How to build a subcontractor list from your Outlook emails

Most of your subcontractor list is already in your team's Outlook: nearly every sub who has sent a quote, answered an RFI or emailed site has left their name, company, phone and email in their email signature. To build the list, put one row per person in one shared place, with their company, trade, role, phone, email, area and when you last heard from them. You can copy them out of Outlook by hand into a spreadsheet, or have Sigbot read the signatures in everyone's Outlook and build one shared list for you.

1. The columns it needs 2. By hand from Outlook 3. From everyone's Outlook

Why your sub list is in your inbox.

Ask for the sub list and you'll often get a spreadsheet nobody has touched since the last big tender. The list people actually work from is in their email.

Nearly every email from a sub, supplier or consultant ends in a signature with the sender's name, job title, company, phone and email, and that mail reaches everyone on the team:

Estimators and precon: quotes, tender returns and replies to ITBs (bid invitations in Canada).
Project managers: RFIs, technical queries and drawings.
Site managers and supervisors: deliveries, permits, snags and O&M manuals.
Buyers and QSs: supplier quotes and orders, valuations and variations.

Each person sees only their own mailbox, and when a site manager leaves, the numbers in their inbox go with them. A useful sub list gathers all of it in one place for the whole team: the site team chasing a foreman and the buyer after a second supplier, not only the estimators building bid lists.

The usual ways to keep a sub list, and where each goes stale.

Each of these works for a while. They go stale for the same reason: someone has to type in every new person, and every change after that.

The usual ways to keep a subcontractor list compared
	Shared spreadsheet	Bid platform's directory	CRM	Outlook contacts	Sigbot
Who's in it	Whoever someone typed in	Firms invited to bid through it	Whoever was entered or logged	The people one person saved	The people whose signatures are in your team's mailboxes
Who can use it	Whoever has the file	People who use the platform	People who use the CRM	One person, unless they share a folder	The whole team, in the browser and the iPhone and Android apps (shared folders on team plans)
Kept up to date	When someone edits a row	When someone edits a record	When someone enters the change	When its owner edits the contact	Checks everyone's mail by itself: daily on paid plans, weekly on Free

Shared spreadsheet

A spreadsheet on a shared drive

Cheap and flexible. Our free subcontractor database template has a Trade drop-down with UK trade packages or MasterFormat divisions.
Where it goes stale: every row is typed by hand, copies drift apart on people's desktops, and nobody updates it when a contracts manager changes their mobile.

Bid platform

The tender or bid platform's own list

Built for sending invitations and collecting bids, it keeps a directory of the firms you invite.
Where it goes stale: the sub's supervisor who emails your site manager, or the supplier your buyer orders from, may never have been invited to bid, so they aren't in it.

CRM

A CRM

It can hold everything, with notes and history, and some log emails for you.
Where it goes stale: only what's entered or logged gets in, so if site managers, buyers and QSs don't use it every day, their contacts never arrive.

Outlook contacts

Everyone's own Outlook contacts

Each person saves the people they deal with, and Outlook exports them to a CSV file.
Where it goes stale: most senders are never saved, and contacts sit in each person's own mailbox. Sharing a contacts folder needs a Microsoft Exchange account and isn't supported in Outlook on the web (the ways to share them).

The columns a sub list needs.

One row per person, not per company: a firm with two estimators and a contracts manager gets three rows. Most of these eight columns come straight from an email signature.

The columns a subcontractor list needs, with a made-up example
	What goes in it	Example (made up)	Where you find it
Company	The firm's name as it trades	Tenterby Groundworks Ltd	The signature
Trade	Their trade package (UK) or MasterFormat division (Canada); more than one if needed	Groundworks, or 31 Earthwork	You decide: signatures rarely say
Contact	One person's first and last name	Tom Ashby	The signature
Role	Job title: estimator, contracts manager, supervisor, accounts	Contracts Manager	The signature
Phone	Office and mobile, in cells formatted as text so Excel keeps them as typed	07700 900318	The signature
Email	The person's own address, not just the firm's info@	tom.ashby@tenterby-groundworks.example	The signature, or the From line
Area	The region they'll work in, kept apart from their office address	Surrey and Hampshire	Their address is in the signature; the area is your call
Last heard from	The date of their latest email	14 Oct 2026	Your inbox

For bid lists, add approval status, insurance expiry and when you last asked them to price. Our free template has all of these, in Excel and CSV.

UK or Canada? UK contractors tend to group subs by trade package: groundworks, M&E, drylining and the rest. In Canada, trades are often sorted by MasterFormat division (03 Concrete, 23 HVAC, 26 Electrical and so on): the numbered list that CSI and Construction Specifications Canada maintain, and that CSI describes as the construction industry's standard language for project documentation across North America. The template and Sigbot's Trade field have both lists.

Every example on this page is fictional: email addresses end in .example and 07700 900318 is in a range set aside for drama.

How to pull a sub list out of Outlook by hand.

Fine for a few dozen subs in one mailbox. Each person has to do it in their own.

1. Find them. Click the Search box at the top of Outlook and search for quote, tender, a package or a job name. To narrow it down:

Search terms for finding subcontractors' emails in Outlook
Type in the Search box	To find
`subject:"tender"`	Mail with that word or phrase in the subject
`from:"tom ashby"`	Everything one person has sent you
`hasattachment:yes`	Only mail with attachments, handy for quotes sent as files
`quote AND groundworks`	Mail with both words. AND, OR and NOT go in capitals

Microsoft's guide covers classic Outlook, new Outlook for Windows and Outlook.com. Outlook returns only the first 1,000 results, so search one package or job at a time.

2. Save each sender as a contact, copying the job title, company and phone numbers from their signature.

Classic Outlook for Windows

Add to Outlook Contacts

Open the email in the reading pane and select the sender's name.
On the profile card, select View more options for interacting with this person, then Add to Outlook Contacts.
Enter the details from their signature, then select Save & Close.

New Outlook and Outlook on the web

Add to contacts

Open the email in the reading pane and select the sender's name.
On the profile card, select More options, then Add to contacts.
Select Edit contact, enter the details from their signature, then select Save.

3. Mark each one's trade with a category. In classic Outlook, go to People, right-click a contact, select Categorize and pick a colour; to name a colour after a trade, select Home > Categorize > All Categories, select the colour, then Rename. In new Outlook and Outlook on the web, select a contact, then Add category on the ribbon or in its More options menu.

4. Export them to a CSV file for Excel. Classic Outlook: File > Open & Export > Import/Export > Export to a file > Comma Separated Values, then the Contacts folder. New Outlook: People > Export contacts. Outlook on the web: People > Manage contacts > Export contacts. Every step for each version. If you'll import the file anywhere later, Microsoft suggests closing it without saving changes.

What it costs. A few minutes a sub. For a few hundred across a team's mailboxes, it's days of typing, and the list starts going out of date the week it's finished.

Or let Sigbot build it from everyone's Outlook.

Sigbot reads the email signatures in Outlook and Microsoft 365 and turns each one into a contact: name, job title, company, phone, email and address. On team plans, everyone connects their own Outlook and you share folders, so the whole team works from one list built from everyone's mail, from site to preconstruction.

Step 1

Everyone connects Outlook

Each person connects their own mailbox with their Microsoft account. The first scan reads the signatures already in it; newsletters and no-reply mail wait in a review queue.

Step 2

Give each sub a trade

Sigbot has a built-in Trade field. Start from the UK trade packages or the Canadian MasterFormat divisions, and put contacts in team folders by trade or by project.

Step 3

Use it on live work

Filter by trade and by distance from a postcode, town or address, select the subs, then copy their emails or open an email in Outlook with them in Bcc. Or export the list to Excel or CSV.

Sigbot's contacts list filtered to the Electrical trade within 50 miles of Leeds, with a Trade column showing each subcontractor's trades

For the whole team. Site and project teams get everyone on the job in one list, buyers get every supplier who has priced work, and precon builds the bid list for a package by trade and area from every sub who has quoted to anyone on the team. Click around a sample sub list, no sign-up.

On every phone. The list is in the iPhone and Android apps, and Caller ID sync can add all your contacts, or one folder, to the phone's own address book and keep them up to date. When a sub's foreman rings, the site manager sees a name and company instead of a number: caller ID from your Outlook contacts.

Who's near the site. Contacts with an address are on a map in the web app and the iPhone app, and in the iPhone app you can search a radius around any site to find who's nearby.

How it stays current. After the first scan, Sigbot checks each connected mailbox for new mail by itself: every day on paid plans, every week on Free. When a newer signature shows a different job title or phone number, it updates the contact and keeps their previous job titles and companies, and it never overwrites what you typed in yourself. Someone who moves firms writes from a new address, so they arrive as a new contact: merge the two from the suggested duplicates (merges can be undone). Bounced addresses are flagged and left out of copied emails and exports; nothing is deleted automatically.

Already keeping a spreadsheet? Import it in the web app with Add Data > Import (Excel/CSV/vCard), Trade included: the details.

It only reads, and IT approves it once. Sigbot works with Outlook and Microsoft 365. It asks Microsoft to read mail (Mail.Read), not to send, move or delete it, and it doesn't write to your Outlook contacts. Microsoft's default setting stops people giving any outside app access to their mail, so most companies have an admin approve Sigbot once, for everyone; its Outlook app is publisher-verified by Microsoft (SIGBOT LTD). Our one-page brief for IT admins has the approval link.

Questions.

How do I build a subcontractor database?

Start from your team's email: nearly every sub who has sent a quote, answered an RFI or emailed site has left their name, company, phone and email in their email signature. Put one row per person in one shared list, with company, trade, contact, role, phone, email, area and when you last heard from them. Copy the details out of Outlook by hand into a spreadsheet, or use a tool such as Sigbot that reads the signatures in everyone's Outlook into one list.

What columns should a subcontractor list have?

Company, trade, contact name, role, phone, email, the area they cover and the date you last heard from them, with one row per person rather than per company. For bid lists, add approval status, insurance expiry and when you last asked them to price.

How do I keep a subcontractor list up to date?

Keep one shared list rather than personal copies, clear bounced addresses after every round of invitations, and update a row when someone writes from a new firm or with a new number. Sigbot checks each connected Outlook mailbox for new mail daily on paid plans (weekly on Free), updates job titles and phone numbers from newer signatures, and flags bounced addresses.

Can I make a subcontractor list from my Outlook contacts?

Yes, for the contacts you've saved: Outlook exports them to a CSV file that opens in Excel (People > Export contacts in new Outlook; File > Open & Export > Import/Export in classic Outlook). Most subs are never saved as contacts, so first add each sender from the profile card on their email, or use a tool that reads the signatures in your mailbox.

Is there subcontractor directory software that works with Outlook?

Sigbot builds a shared subcontractor list from the email signatures in Outlook and Microsoft 365, with a built-in Trade field for UK trade packages or Canadian MasterFormat divisions, in the browser and the iPhone and Android apps, and exports it to Excel or CSV. Bid platforms and CRMs also keep directories, filled in as firms are invited or entered.

Does Sigbot change our Outlook contacts?

No. Sigbot only reads mail, and it doesn't write to anyone's Outlook contacts. The list is in Sigbot, and anyone can export it to Excel or CSV and import that file into Outlook.

Sources.

Every Outlook step above was checked against Microsoft's support pages on 27 October 2026, and the MasterFormat description against CSI's page the same day. Microsoft changes its menus from time to time; if yours look different, these pages have the latest steps.

How to search in Outlook: the search terms, operators in capitals, the versions covered and the 1,000-result limit (checked 27 Oct 2026).
Add, find, edit, or delete a contact in Outlook: adding a sender from the profile card in each version (checked 27 Oct 2026).
Organize your contacts with color categories: categorising contacts and renaming categories (checked 27 Oct 2026).
Import or export contacts in Outlook using a .csv file: the export steps in each version, and closing the file without saving (checked 27 Oct 2026).
Share a contacts folder with others: the Exchange requirement, and no sharing in Outlook on the web (checked 27 Oct 2026).
MasterFormat 2026 (Construction Specifications Institute): what MasterFormat is, its use across North America, and that CSI and Construction Specifications Canada maintain it (checked 27 Oct 2026).

Outlook, Microsoft 365 and Exchange are trademarks of the Microsoft group of companies. MasterFormat® is published by The Construction Specifications Institute (CSI) and Construction Specifications Canada (CSC); Sigbot is not affiliated with CSI or CSC.

Your sub list, from your team's Outlook.

Twenty minutes: how you keep your sub list today, then a look at a sample contractor's list in Sigbot. No slides.

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Keeping a list by hand for now? Get the free subcontractor database template. More on Sigbot for construction, or for Canadian contractors.