Santander mortgages: the published routes that are actually useful in 2026

Santander is not the lender page to read as a generic “large bank with competitive fixed rates” summary. The public pages are more useful when you focus on the routes Santander actually spells out clearly: My First Mortgage for eligible low-deposit buyers, a 60-day Decision in Principle, a defined change-your-deal window for existing customers, published moving-home porting rules, and explicit fixed-rate versus non-fixed overpayment rules.

That makes this a stronger decision page than another thin lender review built around vague rate-shopping language.

Start here

Start with Santander early if:

• you are a first-time buyer trying to make a low-deposit purchase work with a minimum £10,000 deposit
• you want a Decision in Principle that Santander notes is free, instant and valid for 60 days
• you already have a Santander mortgage and want to understand the 4-month lock-in window for a new deal
• you are moving home and want to know whether porting the current rate avoids an early repayment charge
• overpayments matter to your plan and you need a lender that clearly separates fixed-rate allowances from non-fixed unlimited overpayments

Santander is a weaker fit to start with if:

• the property is a flat, new-build home, or in Northern Ireland and you are relying on My First Mortgage
• it is a joint application and both applicants are not first-time buyers, because Santander notes both must be first-time buyers for My First Mortgage
• you want to book a future-dated new deal and still make other mortgage changes before it starts
• you want to overpay a fixed-rate mortgage above the annual allowance without triggering an early repayment charge
• you are really asking a whole-market comparison question rather than a Santander-route question

My First Mortgage

My First Mortgage is the part of Santander that matters most here, because it is much more precise than the broad “good for first-time buyers” label many lender pages use.

Santander notes:

• My First Mortgage is for first-time buyers only
• the minimum deposit is £10,000
• borrowing can be between £190,001 and £500,000
• the maximum loan to value is 98%
• the product uses a 5-year fixed rate
• it is not available for flats, new-build homes or properties in Northern Ireland
• for a joint mortgage, both applicants must be first-time buyers

That is a much tighter route than a generic small-deposit mortgage summary.

Published Santander My First Mortgage point	What it means in practice
Minimum deposit of £10,000	Santander is using a cash-deposit floor, not just a percentage headline.
Maximum 98% loan to value	This is a high-LTV route, but it is still not a no-deposit route.
Borrowing from £190,001 to £500,000	The route is aimed at a specific borrowing band rather than every first-time-buyer case.
Not available for flats or new-build homes	A buyer cannot assume the 98% route works across all first-home property types.
Joint applicants must both be first-time buyers	The route is narrower than a general “joint borrower” first-home option.

Santander also explicitly warns about negative equity risk on low-deposit borrowing. That matters because a 98% page should not be read as pure upside. The lender itself is flagging the downside if property values fall.

Decision in Principle

Santander’s Decision in Principle page is useful because it is very clear on both the convenience and the limit of the tool.

Santander notes:

• the DIP is free
• there is no obligation
• it is valid for 60 days
• you get the decision straight away
• you can download a copy
• you do not need to be a Santander customer to apply
• the online DIP uses a soft search
• the soft search will not affect your credit score
• the later full mortgage application uses a hard credit search

That gives the DIP a clear role: it is a practical early-stage affordability and offer-making tool, not a mortgage approval.

Santander also notes the DIP is useful whether you are:

• buying your first home
• moving home
• remortgaging

That is why this section matters even on a lender page that also has a specific low-deposit product. Santander is telling you that the DIP is a broader entry point than My First Mortgage alone.

Change your deal

Santander is also unusually explicit about what an existing customer can do when the current rate is ending.

Santander notes:

• there are no affordability or income checks
• there are no legal or valuation fees
• there are no new Direct Debits to set up
• you can lock in a new deal 4 months before your current fixed rate ends
• you can change deal if the current deal ends in the next 4 months, has no ERC, or the mortgage is on the Standard Variable Rate or Follow-on Rate

The timing detail is what makes the page useful.

Santander also notes:

• if the new deal is lower than the current one, you may be able to start it straight away or wait until the current deal ends
• if it starts straight away, there is no ERC to pay
• if the new deal is the same or higher, it will be set to start when the current deal ends

There is also an important operational limit here. Santander notes that if you book a new deal to start on a future date, you cannot make other changes to the mortgage until that new deal has started. It specifically notes that includes:

• making an overpayment
• applying for an additional loan
• starting the process of moving home
• arranging a new deal for another loan on the mortgage

That makes Santander’s switch page much more useful as an operations page, not just a retention-rate page.

Moving home

Santander’s moving-home page is another strong reason not to flatten the lender into a generic “can port your mortgage” summary.

Santander notes:

• you may be able to port your current deal to the new property
• if you sell and buy on the same day, you will not pay an ERC on your current fixed rate unless you borrow less
• if you need to borrow more, you can port the current deal for the same amount and choose a new deal for the extra borrowing
• if you borrow the same amount, you will not pay an ERC to port a fixed-rate deal
• if you borrow less, you pay part of the ERC on the amount reduced

Santander also sets out a separate rule for borrowers who choose a new deal instead of porting.

If you have 9 months or less left on the current fixed rate, Santander notes you will not pay an ERC if you borrow the same amount or more than the current mortgage.

That matters because the page is really about structure:

1. Are you porting or taking a new deal?
2. Are you borrowing more, the same, or less?
3. Are you selling and buying on the same day or not?

Santander even goes further for different-day transactions. It notes you may get the ERC refunded if you meet its timing and borrowing conditions after redeeming the old mortgage. That is far more decision-useful than a one-line “porting available” claim.

Overpayments

Santander’s overpayment page is clearer than many lender pages because it splits the rules by mortgage type.

Santander notes:

• on a fixed rate, you can overpay up to 10% of any fixed-rate loan each calendar year
• if you do not use the full allowance, you cannot carry it forward
• the allowance does not reset if you change to a different deal during the same calendar year
• if you are not on a fixed rate, you can make unlimited overpayments without paying an ERC

That already makes the page better than generic “up to 10%” copy, but there is another practical detail.

Santander also notes that if you are eligible to change your deal and want to make an overpayment, you can do both at the same time without paying an ERC or using up your 10% fixed-rate allowance. That is a highly operational rule, and exactly the kind of thing borrowers need on a lender page.

The lender also distinguishes between:

• single overpayments, where you can choose between reducing the term or reducing monthly payments
• regular overpayments, which reduce the term

That is useful because repayment strategy is not just about whether overpayments are allowed. It is about what effect they actually have.

Next steps

• Use the Mortgage Comparison Calculator if the real question is Santander versus the wider market
• Use the First-Time Buyer Advice Page if the real issue is whether a high-LTV first-home route is the right move at all
• Use the Mortgage Deal Ending Guide if your current rate is ending and the switch timing matters more than Santander itself
• Use the Remortgage 2026 Guide if you want to compare Santander’s retention path with wider remortgage options
• Use the Mortgage Overpayment Calculator if the key question is how Santander’s fixed versus non-fixed overpayment rules affect your plan