Do I need to fill in IHT forms?

Markus251

Hello,
My father in law passed away in 2012 and we did probate ourselves back then as everything was very straight forward - just a couple of bank accounts over the banks limit for not needing probate. 

Fast forward to now and my mother in law passed away in December 2025. She was a very simple woman with no debts, and only using one building society all her life for income and savings accounts etc. Her home was fully paid off many years ago and is solely in her name. She had very few possessions and nothing of any value. She lived as though she were very poor, never really spending much on anything apart from day trips out etc.

There is a Will and my partner is Executor and I'm helping her where I can. The Will is very simple, stating upon my mother in laws death everything is left to my partner (her only child). Family are aware of this and there are no disputes. 

The bank accounts amount to approx. 200k and the house is quite run down with refurbished properties in the area selling for a ceiling price of 195k. We haven't had any actual property valuation done yet.

From what we understand, there's no inheritance tax due as everything is left to my mother in laws only daughter and that increases the threshold to 500k.

Because of this, do we still need to fill out the IHT400 form, even though the estate is well under 500k or do we skip that part and simply apply for probate?

When I open up the IHT400 form on the .gov site, a pop up box appears asking if I really do need to fill this form out and am I sure IHT is due. Hence my questions.

Having applied for probate in the past and it being so straight forward, we thought it wouldn't be too complicated this time around. 

Obviously I don't want to be filling out endless numbers of forms if I don't need to.

Any help appreciated and sorry for writing so much, i just wanted to provide a bit of a background as everyone is different

Mark

poseidon1

Markus251 said:

Hello,
My father in law passed away in 2012 and we did probate ourselves back then as everything was very straight forward - just a couple of bank accounts over the banks limit for not needing probate. 

Fast forward to now and my mother in law passed away in December 2025. She was a very simple woman with no debts, and only using one building society all her life for income and savings accounts etc. Her home was fully paid off many years ago and is solely in her name. She had very few possessions and nothing of any value. She lived as though she were very poor, never really spending much on anything apart from day trips out etc.

There is a Will and my partner is Executor and I'm helping her where I can. The Will is very simple, stating upon my mother in laws death everything is left to my partner (her only child). Family are aware of this and there are no disputes. 

The bank accounts amount to approx. 200k and the house is quite run down with refurbished properties in the area selling for a ceiling price of 195k. We haven't had any actual property valuation done yet.

From what we understand, there's no inheritance tax due as everything is left to my mother in laws only daughter and that increases the threshold to 500k.

Because of this, do we still need to fill out the IHT400 form, even though the estate is well under 500k or do we skip that part and simply apply for probate?

When I open up the IHT400 form on the .gov site, a pop up box appears asking if I really do need to fill this form out and am I sure IHT is due. Hence my questions.

Having applied for probate in the past and it being so straight forward, we thought it wouldn't be too complicated this time around. 

Obviously I don't want to be filling out endless numbers of forms if I don't need to.

Any help appreciated and sorry for writing so much, i just wanted to provide a bit of a background as everyone is different

Mark

Acquaint yourself with the 'excepted estates' criteria below -

https://www.gov.uk/valuing-estate-of-someone-who-died/check-type-of-estate

If it applies, your wife can apply for probate online, skipping the entire IHT 400 process.

 This is predicated on your  wife relying   on  the 2 NRBs for FIL and MIL ( total £650k), rather than MIL's  NRB and the Residence nil rate band- RNRB ( total £500k). Trying to claim the RNRB triggers the IHT 400, which seems unnecessary on the numbers you quote.

Keep_pedalling

Assuming your MIL was the main beneficiary from her husband’s estate then you can simply claim the transferable NRB from his estate on the probate application. You would only need to make an IHT return if his NRB was used up on bequests to other people then you will need to complete a return as it is the only way to claim her residential NRB. 

Markus251

Keep_pedalling said:

Assuming your MIL was the main beneficiary from her husband’s estate then you can simply claim the transferable NRB from his estate on the probate application. You would only need to make an IHT return if his NRB was used up on bequests to other people then you will need to complete a return as it is the only way to claim her residential NRB. 

When my father in law passed away, he left everything to my partner. The house was already solely owned by my mother in law. Everything he had was savings accounts around 40k. 

RAS

Did FIL ever have an ownership stake in the house?

poppystar

Markus251 said:

Keep_pedalling said:

Assuming your MIL was the main beneficiary from her husband’s estate then you can simply claim the transferable NRB from his estate on the probate application. You would only need to make an IHT return if his NRB was used up on bequests to other people then you will need to complete a return as it is the only way to claim her residential NRB. 

When my father in law passed away, he left everything to my partner. The house was already solely owned by my mother in law. Everything he had was savings accounts around 40k. 

So there should be a significant part of his NRB unused that you can use now to cover MIL estate.

Markus251

RAS said:

Did FIL ever have an ownership stake in the house?

They jointly owned the house for many years but a couple of years before he passed away, he put himself into a care home and wanted to sell the house to fund that. My mother in law paid him off and the house was transferred into her name. They were still married etc, it was just the house that was exchanged into MIL name. 

Markus251

poseidon1 said:

Markus251 said:

Hello,
My father in law passed away in 2012 and we did probate ourselves back then as everything was very straight forward - just a couple of bank accounts over the banks limit for not needing probate. 

Fast forward to now and my mother in law passed away in December 2025. She was a very simple woman with no debts, and only using one building society all her life for income and savings accounts etc. Her home was fully paid off many years ago and is solely in her name. She had very few possessions and nothing of any value. She lived as though she were very poor, never really spending much on anything apart from day trips out etc.

There is a Will and my partner is Executor and I'm helping her where I can. The Will is very simple, stating upon my mother in laws death everything is left to my partner (her only child). Family are aware of this and there are no disputes. 

The bank accounts amount to approx. 200k and the house is quite run down with refurbished properties in the area selling for a ceiling price of 195k. We haven't had any actual property valuation done yet.

From what we understand, there's no inheritance tax due as everything is left to my mother in laws only daughter and that increases the threshold to 500k.

Because of this, do we still need to fill out the IHT400 form, even though the estate is well under 500k or do we skip that part and simply apply for probate?

When I open up the IHT400 form on the .gov site, a pop up box appears asking if I really do need to fill this form out and am I sure IHT is due. Hence my questions.

Having applied for probate in the past and it being so straight forward, we thought it wouldn't be too complicated this time around. 

Obviously I don't want to be filling out endless numbers of forms if I don't need to.

Any help appreciated and sorry for writing so much, i just wanted to provide a bit of a background as everyone is different

Mark

Acquaint yourself with the 'excepted estates' criteria below -

https://www.gov.uk/valuing-estate-of-someone-who-died/check-type-of-estate

If it applies, your wife can apply for probate online, skipping the entire IHT 400 process.

 This is predicated on your  wife relying   on  the 2 NRBs for FIL and MIL ( total £650k), rather than MIL's  NRB and the Residence nil rate band- RNRB ( total £500k). Trying to claim the RNRB triggers the IHT 400, which seems unnecessary on the numbers you quote.

It looks as though its an excepted estate in our case. Everything is left to MIL only daughter. Savings of 200k and house with an absolute maximum value of 200k and very little possessions, certainly nothing of significant value. She didn't even have a car. It would all total way less than 500k, the threshold for IHT when leaving to daughter. 

I filled out the online check and that came up as no IHT to pay too.

poseidon1

Markus251 said:

poseidon1 said:

Markus251 said:

Hello,
My father in law passed away in 2012 and we did probate ourselves back then as everything was very straight forward - just a couple of bank accounts over the banks limit for not needing probate. 

Fast forward to now and my mother in law passed away in December 2025. She was a very simple woman with no debts, and only using one building society all her life for income and savings accounts etc. Her home was fully paid off many years ago and is solely in her name. She had very few possessions and nothing of any value. She lived as though she were very poor, never really spending much on anything apart from day trips out etc.

There is a Will and my partner is Executor and I'm helping her where I can. The Will is very simple, stating upon my mother in laws death everything is left to my partner (her only child). Family are aware of this and there are no disputes. 

The bank accounts amount to approx. 200k and the house is quite run down with refurbished properties in the area selling for a ceiling price of 195k. We haven't had any actual property valuation done yet.

From what we understand, there's no inheritance tax due as everything is left to my mother in laws only daughter and that increases the threshold to 500k.

Because of this, do we still need to fill out the IHT400 form, even though the estate is well under 500k or do we skip that part and simply apply for probate?

When I open up the IHT400 form on the .gov site, a pop up box appears asking if I really do need to fill this form out and am I sure IHT is due. Hence my questions.

Having applied for probate in the past and it being so straight forward, we thought it wouldn't be too complicated this time around. 

Obviously I don't want to be filling out endless numbers of forms if I don't need to.

Any help appreciated and sorry for writing so much, i just wanted to provide a bit of a background as everyone is different

Mark

Acquaint yourself with the 'excepted estates' criteria below -

https://www.gov.uk/valuing-estate-of-someone-who-died/check-type-of-estate

If it applies, your wife can apply for probate online, skipping the entire IHT 400 process.

 This is predicated on your  wife relying   on  the 2 NRBs for FIL and MIL ( total £650k), rather than MIL's  NRB and the Residence nil rate band- RNRB ( total £500k). Trying to claim the RNRB triggers the IHT 400, which seems unnecessary on the numbers you quote.

It looks as though its an excepted estate in our case. Everything is left to MIL only daughter. Savings of 200k and house with an absolute maximum value of 200k and very little possessions, certainly nothing of significant value. She didn't even have a car. It would all total way less than 500k, the threshold for IHT when leaving to daughter. 

I filled out the online check and that came up as no IHT to pay too.

You keeping mentioning the £500k threshold, but if you read the excepted estates criteria properly (and the  associated links thereto)  that is predicated on a £650k threshold ( husband and wife's £325k NRBs).

If you are going to rely on the mother's £325k NRB plus her £175k Residence NRB then that will trigger completion of the IHT 400 even where no IHT payable ( see below). I thought that was clear from my original post.

https://www.gov.uk/guidance/check-if-you-can-get-an-additional-inheritance-tax-threshold#:~:text=How to claim the residence,form and the form IHT435.

However that is now a moot point.

From the additional information you supplied, £40k of husband's NRB was used up on gift to your spouse so you only have £285k of his remaining NRB to deploy in addition to MIL's own £325k ( total £610k). 

As you will see from the additional guidance below, where the transferable NRB from the 1st to die is less than the full £325k,  the estate of the 2nd spouse to die no longer qualifies for 'excepted estate' treatment, and you are back to having to complete IHT 400.

https://www.gov.uk/guidance/transferring-unused-basic-threshold-for-inheritance-tax

Which ever route you choose to follow, on a value of say £400k for MIL's estate, IHT 400 is necessary.

Keep_pedalling

poseidon1 said:

Markus251 said:

poseidon1 said:

Markus251 said:

Hello,
My father in law passed away in 2012 and we did probate ourselves back then as everything was very straight forward - just a couple of bank accounts over the banks limit for not needing probate. 

Fast forward to now and my mother in law passed away in December 2025. She was a very simple woman with no debts, and only using one building society all her life for income and savings accounts etc. Her home was fully paid off many years ago and is solely in her name. She had very few possessions and nothing of any value. She lived as though she were very poor, never really spending much on anything apart from day trips out etc.

There is a Will and my partner is Executor and I'm helping her where I can. The Will is very simple, stating upon my mother in laws death everything is left to my partner (her only child). Family are aware of this and there are no disputes. 

The bank accounts amount to approx. 200k and the house is quite run down with refurbished properties in the area selling for a ceiling price of 195k. We haven't had any actual property valuation done yet.

From what we understand, there's no inheritance tax due as everything is left to my mother in laws only daughter and that increases the threshold to 500k.

Because of this, do we still need to fill out the IHT400 form, even though the estate is well under 500k or do we skip that part and simply apply for probate?

When I open up the IHT400 form on the .gov site, a pop up box appears asking if I really do need to fill this form out and am I sure IHT is due. Hence my questions.

Having applied for probate in the past and it being so straight forward, we thought it wouldn't be too complicated this time around. 

Obviously I don't want to be filling out endless numbers of forms if I don't need to.

Any help appreciated and sorry for writing so much, i just wanted to provide a bit of a background as everyone is different

Mark

Acquaint yourself with the 'excepted estates' criteria below -

https://www.gov.uk/valuing-estate-of-someone-who-died/check-type-of-estate

If it applies, your wife can apply for probate online, skipping the entire IHT 400 process.

 This is predicated on your  wife relying   on  the 2 NRBs for FIL and MIL ( total £650k), rather than MIL's  NRB and the Residence nil rate band- RNRB ( total £500k). Trying to claim the RNRB triggers the IHT 400, which seems unnecessary on the numbers you quote.

It looks as though its an excepted estate in our case. Everything is left to MIL only daughter. Savings of 200k and house with an absolute maximum value of 200k and very little possessions, certainly nothing of significant value. She didn't even have a car. It would all total way less than 500k, the threshold for IHT when leaving to daughter. 

I filled out the online check and that came up as no IHT to pay too.

As you will see from the additional guidance below, where the transferable NRB from the 1st to die is less than the full £325k,  the estate of the 2nd spouse to die no longer qualifies for 'excepted estate' treatment, and you are back to having to complete IHT 400.

https://www.gov.uk/guidance/transferring-unused-basic-threshold-for-inheritance-tax

Which ever route you choose to follow, on a value of say £400k for MIL's estate, IHT 400 is necessary.

Based on the link provided I don’t think that applies to deaths that occurred after 31 Dec 2021 as per the following excerpt. 

Where full details are not needed — excepted estates

If it’s an excepted estate check which process you need to follow.

For deaths on or before 31 December 2021 you can only make a claim to transfer the full unused threshold with form IHT217.

If you’re transferring less than the full unused threshold, you’ll no longer qualify as an excepted estate. You must make a full return of estate with form IHT400 and form IHT402.

For deaths on or after 1 January 2022 you:

• can transfer any unused amount
• should claim when you apply for probate

poseidon1

Keep_pedalling said:

poseidon1 said:

Markus251 said:

poseidon1 said:

Markus251 said:

Hello,
My father in law passed away in 2012 and we did probate ourselves back then as everything was very straight forward - just a couple of bank accounts over the banks limit for not needing probate. 

Fast forward to now and my mother in law passed away in December 2025. She was a very simple woman with no debts, and only using one building society all her life for income and savings accounts etc. Her home was fully paid off many years ago and is solely in her name. She had very few possessions and nothing of any value. She lived as though she were very poor, never really spending much on anything apart from day trips out etc.

There is a Will and my partner is Executor and I'm helping her where I can. The Will is very simple, stating upon my mother in laws death everything is left to my partner (her only child). Family are aware of this and there are no disputes. 

The bank accounts amount to approx. 200k and the house is quite run down with refurbished properties in the area selling for a ceiling price of 195k. We haven't had any actual property valuation done yet.

From what we understand, there's no inheritance tax due as everything is left to my mother in laws only daughter and that increases the threshold to 500k.

Because of this, do we still need to fill out the IHT400 form, even though the estate is well under 500k or do we skip that part and simply apply for probate?

When I open up the IHT400 form on the .gov site, a pop up box appears asking if I really do need to fill this form out and am I sure IHT is due. Hence my questions.

Having applied for probate in the past and it being so straight forward, we thought it wouldn't be too complicated this time around. 

Obviously I don't want to be filling out endless numbers of forms if I don't need to.

Any help appreciated and sorry for writing so much, i just wanted to provide a bit of a background as everyone is different

Mark

Acquaint yourself with the 'excepted estates' criteria below -

https://www.gov.uk/valuing-estate-of-someone-who-died/check-type-of-estate

If it applies, your wife can apply for probate online, skipping the entire IHT 400 process.

 This is predicated on your  wife relying   on  the 2 NRBs for FIL and MIL ( total £650k), rather than MIL's  NRB and the Residence nil rate band- RNRB ( total £500k). Trying to claim the RNRB triggers the IHT 400, which seems unnecessary on the numbers you quote.

It looks as though its an excepted estate in our case. Everything is left to MIL only daughter. Savings of 200k and house with an absolute maximum value of 200k and very little possessions, certainly nothing of significant value. She didn't even have a car. It would all total way less than 500k, the threshold for IHT when leaving to daughter. 

I filled out the online check and that came up as no IHT to pay too.

As you will see from the additional guidance below, where the transferable NRB from the 1st to die is less than the full £325k,  the estate of the 2nd spouse to die no longer qualifies for 'excepted estate' treatment, and you are back to having to complete IHT 400.

https://www.gov.uk/guidance/transferring-unused-basic-threshold-for-inheritance-tax

Which ever route you choose to follow, on a value of say £400k for MIL's estate, IHT 400 is necessary.

Based on the link provided I don’t think that applies to deaths that occurred after 31 Dec 2021 as per the following excerpt. 

Where full details are not needed — excepted estates

If it’s an excepted estate check which process you need to follow.

For deaths on or before 31 December 2021 you can only make a claim to transfer the full unused threshold with form IHT217.

If you’re transferring less than the full unused threshold, you’ll no longer qualify as an excepted estate. You must make a full return of estate with form IHT400 and form IHT402.

For deaths on or after 1 January 2022 you:

• can transfer any unused amount
• should claim when you apply for probate

Good catch KP.

Easy to get caught out with the ever shifting probate reporting parameters.

Seems OP can indeed bypass IHT as long as he sticks to MIL & FIL's respective NRBs and ignore MIL's Residence NRB.