An internal move and an external move solve different problems

They are not the same transaction

When a role stops working, the choice is usually framed as staying versus leaving, with an internal move treated as the cheaper version of leaving. That framing hides the actual difference, which is about what carries over. An internal move keeps your accumulated context and reputation and changes the work. An external move discards both and changes everything, including the things you had stopped noticing were problems.

Which one is right depends entirely on where the problem is located. If the work has gone flat but the organisation is sound, discarding your standing to fix the work is an expensive way to solve it. If the problem is the organisation — how it makes decisions, what it rewards, whether it is growing — then an internal move relocates you within the same constraint and typically fails within a year.

What an internal move preserves

The underrated asset is context: knowing who actually decides things, which systems are load-bearing, what has already been tried, and which promises the organisation keeps. That knowledge took you a year or more to build and it is not transferable. In a new team internally you are productive in weeks rather than months, which is visible to everyone and buys you goodwill immediately.

Reputation carries too, though less completely than people assume. It travels through whoever your new manager asks about you, so it is a matter of a few conversations rather than an institutional record. That makes leaving your current team well unusually important — an internal move where your old manager is lukewarm is worse than arriving as a stranger.

There is also a practical asymmetry in how the two are judged. Internal moves are usually assessed on evidence people have actually seen, while external hiring is assessed on interviews and a document. If your strengths show up better in sustained work than in a two-hour conversation, internal routes will treat you more kindly.

What an external move resets

Changing employer resets your pay against the market, and that is the honest reason it often produces a larger increase than internal progression. Internal increases are bounded by the band structure and the annual pot; an external offer is bounded only by what the new employer is willing to pay for the role. This is a structural feature rather than a scandal, and it does not require anyone to be behaving badly.

It also resets assumptions about you. If you joined as a graduate and half the building still thinks of you that way, a new employer meets you as whatever you currently are. That reset is genuinely valuable for people whose capability has outgrown their internal reputation, and it is one of the few ways to fix that problem at all.

The cost is everything the context gave you, plus real risk. You are trusting an interview process to tell you what a place is like, and interviews are a poor instrument for that. Some proportion of external moves land somewhere worse, which is the part that rarely gets said.

A rough way to decide

Ask what specifically you want to be different, and then ask whether that thing is a property of the team or of the organisation. Dull work, a bad manager and a narrow remit are usually team-level and often fixable internally. Pay that is structurally below market, an organisation that is shrinking, a culture that does not promote people like you, or an industry you no longer want to be in are organisation-level and are not.

One caution about internal moves: they are frequently slower than advertised. Your current manager may have delivery reasons to delay a transfer, and there may be a convention about how long you must have been in post. Find out the actual rules early, because an internal process that drags for six months while you wait politely is a common and avoidable waste.

Doing either without damage

For an internal move, the sequence matters. Talking to a hiring manager in another team before telling your own is normal in some organisations and a serious breach in others, and getting this wrong is one of the few ways to genuinely harm yourself. Find out the norm before you start, from someone who has done it.

For an external move, resign only when the offer is in writing and any conditions are settled, and keep your reasons for leaving neutral in every conversation. The set of people who work in your field is smaller than it appears from inside a large employer, and the person interviewing you in six years may well be someone you worked with this month.