The cost of a £300,000 mortgage is an important factor to consider, especially in the context of the ever-increasing cost of living in the UK. With the average house price in the country slightly over £300,000, it is crucial to understand the financial implications of such a substantial loan.

Strive Mortgages are experts in all things mortgages, we offer bespoke, high quality, award winning advice. 

If you’re a interested in exploring your mortgage options get in touch with one of our expert brokers on 01273 002697 or email [email protected] 

Cost of a £300k mortgage 

When it comes to determining the cost of a mortgage, several criteria come into play. These factors include the income multiple that lenders typically consider, the borrower’s credit score, the required deposit, the income-to-outgoings ratio, the borrower’s age, and the mortgage term.

One key factor that lenders consider when determining the cost of a mortgage is the borrower’s credit score. A higher credit score indicates to lenders that the borrower is more likely to make timely payments and manage their finances responsibly. This can result in lower interest rates and better loan terms for the borrower. On the other hand, a lower credit score may lead to higher interest rates or even difficulty in securing a mortgage.

Another important aspect that plays a significant role in mortgage cost is the required deposit. Lenders often require borrowers to put down a deposit, typically a percentage of the property’s purchase price. The size of the deposit can impact the interest rate offered by the lender, with a larger deposit usually resulting in a lower interest rate. Additionally, a larger deposit can also reduce the overall amount borrowed, leading to lower monthly payments and less interest paid over the life of the loan.


In most cases, lenders calculate the maximum mortgage amount by applying the income multiple, which is usually between 4.5 and 5.5 times the borrower’s income. For a £300,000 mortgage, this translates to an income range of £54,500 to £66,666.

However, other factors such as the credit score, deposit amount, income-to-outgoings ratio, age, and term also play a crucial role in determining the final cost of the mortgage.

When it comes to credit scores, a higher score typically results in more favourable mortgage terms, such as lower interest rates. Lenders use credit scores to assess the borrower’s creditworthiness and likelihood of repaying the loan on time. A good credit score not only opens up more mortgage options but can also save the borrower thousands of pounds over the life of the loan.

Additionally, the deposit amount can significantly impact the mortgage terms. A larger deposit means the borrower is borrowing less money relative to the property’s value, which can lead to lower interest rates and monthly payments. It also reduces the lender’s risk, making them more inclined to offer competitive rates. Saving up for a larger deposit can be a strategic move for borrowers looking to secure a more affordable mortgage in the long run.

Factors on How Much It Will Cost

Various factors influence the overall cost of a £300,000 mortgage. These factors include the borrower’s age, the chosen mortgage term, the size of the deposit, the interest rate, the credit score, the repayment type, and the specific mortgage product.

For instance, the age of the borrower at the time of taking out the mortgage can impact the term length available. Typically, lenders have a maximum term of 35 to 40 years. Alternatively, the mortgage term may span until the borrower’s planned retirement age or until the age of 70 or 75, depending on the plausibility.

The size of the deposit also plays a crucial role in determining the cost of the mortgage. A larger deposit can result in lower monthly repayments and a better interest rate, ultimately reducing the overall cost of borrowing. Lenders often offer more competitive deals to borrowers with higher deposit amounts, as it signifies lower risk for them.

Moreover, the credit score of the borrower significantly affects the cost of the mortgage. A higher credit score typically leads to lower interest rates and better mortgage terms, saving the borrower money over the life of the loan. Lenders use credit scores to assess the risk of lending to an individual, with lower scores indicating higher risk and potentially higher costs.

Monthly cost examples

As discussed above, the monthly costs of a £300k mortgage  can vary considerably based on certain factors. The chart below shows the impact of increasing interest rates on a £300,000 mortgage over various terms. Use our Mortgage payment Calculator for alternative borrowing amounts and terms. 

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Product Fees

It is important to consider any product fees associated with the mortgage. These fees can range from £0 up to £999 or even higher as a percentage of the mortgage balance. While paying larger product fees might secure a lower interest rate, it is worth noting that these fees can often be added to the mortgage, increasing the overall cost in the long run.

What Rates Are Available?

The rates available for a £300,000 mortgage depend on various factors, including the market conditions at the time of application, the chosen mortgage type, and the borrower’s creditworthiness and deposit amount.

Lenders typically offer fixed-rate and variable-rate mortgages, each with its own advantages and drawbacks. Fixed-rate mortgages provide stability by keeping the interest rate constant throughout a specified period, while variable-rate mortgages fluctuate with market conditions.

What Term Can I Take Over?

When considering a mortgage, it is important to understand the maximum term available. Lenders generally offer a maximum term of 35 to 40 years. However, borrowers can also choose a term that aligns with their planned retirement age or until they reach the age of 70 or 75.

The ultimate decision on the mortgage term will depend on the borrower’s financial situation, long-term goals, and the plausibility of a mortgage beyond their planned retirement age.

How Can I Reduce Payments?

If you are looking to reduce the monthly payments on your mortgage, there are several strategies you can employ. These include opting for a longer mortgage term, providing a larger deposit, improving your credit score, shopping around for the best rates, and seeking the guidance of a mortgage broker.

A longer mortgage term can spread the repayments over a more extended period, reducing the monthly financial burden. Additionally, a larger deposit can help lower the loan-to-value ratio, potentially leading to better interest rates. Improving your credit score and shopping around for competitive rates can also yield significant savings over the life of the mortgage.

Working with a mortgage broker, such as Strive Mortgage Brokers, can provide access to a wide range of lenders and potentially secure better rates. Moreover, a broker can guide you throughout the mortgage application process, providing valuable expertise and support.

How Can Strive Mortgage Brokers Help?

At Strive we will be instrumental in helping you find the best mortgage deal available. As experienced professionals in the mortgage industry, we have access to a broad network of lenders and can leverage their expertise to secure more favourable rates and terms.

Furthermore, We understand the complexities of the mortgage application process. They can guide you through each step, ensuring that you have a complete understanding of the costs involved and helping you navigate any potential obstacles along the way. With their knowledge and support, you can have peace of mind throughout the mortgage journey.

If you’re  interested in exploring your mortgage options get in touch with one of our expert brokers on 01273 002697 or email [email protected] 


Here are some frequently asked questions about the cost of a £300,000 mortgage:

How much is a £300k mortgage per month?

The monthly payment on a £300k mortgage depends on factors such as interest rate, term length, and type of mortgage. For example, a 30-year mortgage at a 3% interest rate would result in a monthly payment of around £1,264. However, it’s crucial to consult with a mortgage advisor for personalised estimates.

Can I get a £300k mortgage on interest-only?

Yes, it’s possible to obtain a £300k mortgage on an interest-only basis, but this is typically subject to certain conditions such as a minimum 25% deposit and other eligibility criteria determined by the lender.

Can I get a 40-year mortgage  term?

Yes, some lenders offer mortgage terms of up to 40 years. However, eligibility for a 40-year term may depend on factors such as your age, income, and other criteria set by the lender.

Can I get 5.5 times my income for a mortgage?

Yes, it’s possible to secure a mortgage of up to 5.5 times your income. However, lenders often require a higher income, such as above £75,000, to qualify for this amount. Additionally, other factors such as credit history, debt-to-income ratio, and employment stability may also influence the lender’s decision.


Contact us todayand we’ll work hard on your behalf to find you a competitive mortgage.

For more information on mortgages for contractors, please contact a member of the Strive team, by emailing [email protected] or call us on 01273 002697.