Published 2026-07-19 · Contractor Mortgage Guide · Written and reviewed by Phillip Wakeling-Smith (CeMAP)

Going permanent mid-application: does taking a perm job help or sink your mortgage?

Quick answer: Changing employment between application and completion — contractor to permanent, or just changing clients — is a material change you must disclose, and it sends underwriting back to the start on your new income. Counter-intuitively, going permanent often hurts in the short term: your assessed income can drop (perm salaries usually undercut annualised day rates) and a probation period is a decline reason at plenty of lenders. If you can control the timing, the clean options are complete first, then switch — or switch first, pass probation, then apply. The messy middle is where purchases fall apart.

Why "more stable" can assess worse

A £500/day contract assessed on a 48-week annualisation is £120,000 of income. The permanent version of that same role might pay £85,000 — a ~30% cut in assessable income the moment underwriting re-runs, which can shrink the loan below the purchase price with your chain already formed. Run both versions of yourself through the day-rate calculator and the contract-vs-permanent calculator before accepting anything.

Add probation: many lenders won't lend (or want conditions) inside a probation period, and a brand-new perm role has no payslip history. The contractor version of you had 18 months of invoices; the permanent version has an offer letter.

Do you have to tell the lender?

Yes. Mortgage offers are made on your declared circumstances, and applications/declarations require you to notify material changes before completion — employment change is squarely material. Beyond the obligation, it surfaces anyway: lenders re-verify employment before completion often enough that betting on silence risks the worst outcome — an offer withdrawn after exchange, when you're contractually committed to buy.

The honest frame: this isn't "should I disclose", it's "how do I time the change so there's nothing awkward to disclose".

Timing playbook

Offer not yet accepted on the new job:

• Completing within weeks? Ask the new employer for a start date after completion. A start date is the cheapest mortgage fix there is.
• Months from completing (long new-build timeline, slow chain)? Consider which version of you the lender should meet — it may be worth applying after the switch at a lender comfortable with new-role applicants (some accept a signed contract + first payslip; a few will use a future contract before day one).

Already applied, offer issued, now switching:

• Tell your broker immediately — before resignation if possible. They can check whether the new package re-passes affordability at your lender, or whether a different lender reads the new situation better.
• Expect: new employment references, possibly a new credit check, revised offer. Build the delay into your chain conversations early.

Contract ending (not by choice) mid-application:

• A gap is also a material change. The contract history and gaps guide covers how lenders read gaps — and if you're mid-purchase, a quickly-signed renewal or new contract restores more than you'd think.

The reverse move (perm → contracting) mid-application is harsher: you'd be a day-one contractor at most lenders — very few lend on that (see first-time contractor mortgages). If you're buying, complete before you leap.

The ambiguous-letter trap

A related killer from real cases: applications declined at final stage because an employer's or agency's reference letter said renewal was "not guaranteed" — technically true of every contract, fatal on paper. If a reference is requested, ask the writer to state facts (current rate, history of renewals, current contract end date) rather than speculating about the future in either direction. Underwriters can weigh a track record; a letter that volunteers doubt gives them nothing to work with.

FAQ

Do I have to tell my mortgage lender if I go permanent before completion?

Yes — employment change is a material change and your application obliges you to disclose it before completion. Lenders also re-check employment at completion frequently enough that non-disclosure risks withdrawal after exchange, the most expensive possible failure.

Will going permanent improve my mortgage application?

Eventually, at some lenders — but usually not immediately. Assessed income often falls versus an annualised day rate, and probation periods restrict lender choice. Once you've passed probation with payslips behind you, the perm profile is straightforwardly strong.

Can I get a mortgage during a probation period?

At some lenders, yes — particularly with a strong same-field history and no break in earnings. Others hard-decline until probation ends. It narrows the pool exactly when you can least afford it, which is why timing the switch around completion is the better tool.

My completion is months away (new build). Should I delay the new job?

This is the highest-risk version — a long build plus a job change is the classic offer-expiry-plus-re-underwriting collision. Read our sister site's lender-by-lender offer extension guide alongside your lender's expiry terms, and make the job-timing decision with your broker holding both calendars.