ChatGPT Team 基礎 2026：ChatGPT Business ワークスペース登録と席位

OpenAI 公式に沿った Team/Business 概要、登録手順、席位と初週設定。

小チームが chatgpt.com で共有 WS・集中請求・管理が欲しいなら、OpenAI ヘルプは旧 ChatGPT Team を 2025-08-29 に ChatGPT Business へ改名したと記載。既存 Team WS は Business へ移行。

本稿は Help Center 8792828・8542115・8980713・8542216 のみ：chatgpt.com/team-sign-up で最低2有料席、Standard/Premium、招待手順。価格は chatgpt.com 決済表示；USD はヘルプ引用。

What ChatGPT Business officially is

Help text describes ChatGPT Business as a self-serve plan for organizations: a shared ChatGPT workspace with centralized billing, admin controls for users and access, usage visibility and spend controls, and access to ChatGPT, ChatGPT Work, and Codex depending on seat type.

FAQ text requires at least two paid Standard or Premium seats (for example one Standard plus one Premium). New subscriptions from August 24, 2026 cap at 200 combined Standard and Premium seats; older workspaces may keep prior limits. For invoices, POs, wires, or Enterprise controls, help text points to sales-led plans instead of self-serve Business.

Sign up for a Business workspace on chatgpt.com

1. 1

   Open the official signup page

   Visit chatgpt.com/team-sign-up in a browser (Help Center article 8980713). Sign in with the OpenAI account that will be workspace Owner. Do not use shared or resold accounts.

2. 2

   Choose Business and seat capacity

   If plan options appear, pick Business. On checkout, select counts of Standard and/or Premium seats, monthly or annual billing, and review the total. Help text says buying extra Standard seats does not upgrade your own seat to Premium—you must choose or assign Premium seats explicitly.

3. 3

   Pay and become Owner

   Complete checkout with your payment method. Help text says you receive a ChatGPT Business workspace and the Owner role. Added seats charge immediately on a prorated basis; seat reductions usually take effect at the next billing cycle.

4. 4

   Invite teammates—or accept an invite

   If your company already has Business, ask an owner for an invitation and accept with the invited email. New workspaces invite members by role and seat type (8542216). Without a matching paid seat, teammates can request access until an owner assigns or purchases capacity.

Workspaces, roles, and seat assignment

Help text defines a workspace as a distinct ChatGPT environment with its own settings, members, and resources. Switch workspaces from the profile menu on web or the sidebar on mobile. Business supports Owner, Admin, Analytics viewer, and Member roles; each user gets a Standard or Premium seat assignment.

First-week checklist after signup

1. 1

   Verify workspace billing

   Owners review seat counts, types, and billing cadence under Workspace settings → Billing. Mix Standard and Premium here; reassigning already-paid seats does not add charges.

2. 2

   Invite members with seat types

   Invite by email with roles and Standard or Premium seats. Bulk CSV import is documented in 8542216 (email, role, seat type columns).

3. 3

   Decide on personal workspace merge

   Article 8980713 says joining Business does not auto-migrate content. Keep personal separate or follow 8801890 to copy supported content into Business—you cannot pick individual chats; merged personal workspaces deactivate but data is not deleted.

4. 4

   Try shared team features

   Standard seats include GPTs, Projects, Company Knowledge, Deep Research, Codex, and more per overview text. When you need a quick team sketch after a ChatGPT brief, wbstorm is a room ID—see 部屋の作成と参加. For personal Plus, see ChatGPT Plus サブスクリプションガイド; for Projects, ChatGPT Projects ハウツー.

# Sources (OpenAI Help Center)
# 8792828 — ChatGPT Business Overview
# 8542115 — ChatGPT Business General FAQ
# 8980713 — Sign up (chatgpt.com/team-sign-up)
# 8542216 — Managing members, seat types, roles
# Team renamed Business: 2025-08-29 (FAQ)
# Price: checkout on chatgpt.com; USD from help articles