Open several Google accounts in one browser at once

Two Google accounts in one browser is a solved problem right up until the moment a shared Drive link opens under the wrong identity and shows a request access screen. That screen is the reason people go looking for a better arrangement. The account switcher in the top right corner is not broken, but it does something more limited than it appears to, and knowing exactly what it does explains every strange thing that follows.

What the account switcher really does

Signing a second Google account into the same browser adds a second identity to one cookie jar. Both sessions exist at the same time, and Google keeps track of them with an index number. The first account signed in becomes zero, the second becomes one, and so on. That number shows up in the address bar of most Google properties as a path segment: mail.google.com slash u slash zero, mail.google.com slash u slash one.

That index is the whole mechanism. When a link arrives without an index in it, and most links do arrive that way, Google has to guess. It resolves to the default account, which is the one that signed in first, regardless of which window was in front or which account was used five seconds earlier. This is why a document that opens perfectly for the person who sent it lands on an access request for the person who received it.

The index is also unstable in one specific way. Signing out of everything and signing back in a different order renumbers the accounts. Bookmarks that were saved with a hard coded index then point at whichever account now holds that slot. Anyone who has bookmarked a specific inbox and later found it opening someone else's mail has met this behaviour.

The switcher gives one browser session several identities. It does not give it several sessions.

Where multi-login stops working

Google's own products handle the index reasonably well. Mail, Drive, Calendar, and Docs all understand it and mostly keep the right account attached to the right tab. The trouble starts at the edges.

Third party sites that offer sign in with Google receive whichever account the browser considers default at that moment. Many of them do not expose an index at all, so there is no way to correct the choice other than changing which account is default, which means signing everything out and back in.

Meet and YouTube behave differently from the rest, and account choice there often has to be made on the page itself rather than through a link. Some administrative consoles refuse the multi-login arrangement outright and demand a session with exactly one identity in it.

Then there is the workspace policy case. An organisation can restrict which accounts may be used inside its services, and a personal account sitting in the same cookie jar can be enough to trip that check. The error message in that situation rarely says what is actually wrong.

None of this is fixable by being careful with clicks. The cause is that one browser profile holds one set of cookies, and cookies are the thing being asked to represent two people.

The five arrangements, and what each one costs

Arrangement	Separate cookies	Separate extensions	Own icon in the Dock	Survives a restart	Setup effort
Second account in the switcher	No	No	No	Yes	One minute
Second browser profile	Yes	Yes	No	Yes	Five minutes
Incognito window	Yes	Mostly off	No	No	None
A second browser application	Yes	Yes	Yes	Yes	Fifteen minutes
One window per web app	Yes	Yes	Yes	Yes	Fifteen minutes

The switcher is fastest and leakiest, and it is the right answer for a personal account that is checked twice a day. Incognito is a good way to test how a page looks to a logged out visitor and a poor way to run a second identity, because it forgets everything on close and most extensions are disabled inside it by default.

A second browser profile is the correct answer to the technical question. Two profiles are, for practical purposes, two browsers that share an application binary: separate cookies, separate history, separate saved passwords, separate extensions. A link opened inside a profile can only resolve to an account that profile knows about, which removes the guessing entirely.

Everything after that row is about ergonomics rather than isolation. Separate profiles fix the identity problem and leave a different one behind, described further down.

Setting up a second profile on a Mac

Open the profile chip at the top right of the browser window, add a profile, and sign it into the second Google account. Two choices inside that flow matter more than they look.

The first is the colour and the name. The window frame gets tinted with the colour chosen, and since two windows of the same browser are otherwise identical, that tint is the only thing distinguishing them at a glance. Colours that are far apart work. Two shades of blue do not.

The second is whether to enable sync in the new profile. Sync carries bookmarks, passwords, and extensions between machines, and it will also carry a client's tooling onto a personal laptop later without asking again. If the second profile exists to keep a client's environment sealed, leaving sync off in that profile is the conservative choice.

Profile data lives under the browser's support directory in folders named Default, Profile 1, Profile 2, and so on. Those folder names have nothing to do with the display names shown in the interface, and the mapping between the two sits in a state file in the same directory. This distinction becomes important the moment a script or shortcut is involved, because launch flags address the folder name and never the display name.

A specific profile can be launched from the command line with a profile directory flag, and a URL added to that command opens in that profile. Wrapping that in a small launcher gives a one click route into the right identity, which is the piece that makes profiles usable rather than merely correct.

The problem profiles do not solve

Profiles separate the sessions perfectly and separate nothing else. On macOS every window still belongs to one application. Command Tab moves between applications and therefore cannot move between profiles. Mission Control groups the windows together. The Dock shows one icon. Notification permission is granted to the application, not to the profile inside it.

The practical result is a setup that is technically right and still feels wrong. Two identical windows sit in the switcher with the same icon, and telling them apart depends on noticing a tint in the frame while moving quickly. Links clicked from outside the browser, in a mail client or a chat app, open in whichever profile the system considers default, which puts the link back in front of the wrong account after all that work.

This is where a different shape of tool becomes relevant. Instead of one application holding many profiles, each web app gets its own window and its own isolated storage, so switching identity is switching window. That model is described on Workspaces, and the list of services already set up for it is on Supported apps. The same isolation is what lets two accounts of one service stay signed in at the same time without either one evicting the other.

Several products occupy this category and they differ in ways worth checking before paying for any of them, particularly around memory use, notification handling, and which platforms are supported. Compared with Wavebox and Compared with Shift set the differences out item by item.

When an organisation's rules reject the arrangement

Some of the failures blamed on the browser are policy decisions made by an administrator on the other side. A managed Google Workspace domain can restrict which accounts are allowed to be signed in on a device or inside a session, and a personal account sharing the same cookie jar is enough to trigger that restriction.

The symptoms are recognisable once the cause is known. A sign in that loops back to the account chooser without an explanation. A message about the account not being allowed, phrased as though the account does not exist. An administrative console that works in a private window and refuses in the normal one. A device that is asked to enrol in management before access is granted, which is a request that should never be accepted on personal hardware.

The remedy is separation rather than persuasion. A managed account belongs in a container of its own, where it is the only identity present, so that whatever check the organisation runs sees exactly what it expects. This is one of the situations where a second profile is not a convenience but a requirement, because no amount of careful clicking will satisfy a policy that inspects the session.

The same logic applies in reverse. A personal account left signed in alongside a managed one can be captured by rules the person never agreed to, including device management, forced extension installs, and retention policies that reach into browsing data. Keeping personal identity out of a work container is a defensive measure, not a tidiness preference.

Anyone dealing with more than one managed domain, which is common among contractors, will find that the number of containers needed matches the number of organisations rather than the number of accounts. Two accounts belonging to the same organisation can usually share a container safely. Two accounts belonging to two organisations should not.

Habits that stop the wrong account opening

Whatever separation is chosen, a few habits remove most of the remaining friction.

Keep the account that receives shared links as the default, meaning the first one signed in. Most incoming links carry no index, so the default is where they land, and it should be the account most likely to have access.

When sending a link to someone else, strip the index out of the URL before sending. A link containing a specific index will try to open in that slot on the recipient's machine, where it belongs to a different person entirely.

Bookmark with the index included for personal use, and understand that those bookmarks break if the accounts are ever renumbered. Anything shared with a colleague should have the index removed.

Give the browser windows visible differences: distinct colours, distinct pinned tabs, distinct positions on screen. Identity that has to be checked deliberately will eventually go unchecked.

What to change first

The fastest improvement is deciding which account is the default and rebuilding the sign in order around it, because that single setting determines where every index free link lands. Do that before installing anything.

If links still keep arriving in the wrong place after that, the next move is separating the containers rather than tuning one of them, and SpaceDeck is one way to give each account its own window. The costs are listed on Pricing.