EX-99.19a-1

MFS® Intermediate High Income Fund

P.O. Box 43078

Providence, RI 02940-3078

Notice to shareholders — Source of distribution

Distribution period	May-2024
Distribution amount per share	$0.01449

The following table sets forth the estimated amounts of the current distribution and the cumulative distributions paid this fiscal year to date from the following sources: net investment income, net realized short-term capital gains, net realized long-term capital gains and return of capital or other capital source. The fund’s fiscal year begins each December 1st. All amounts are expressed per common share.

		% Breakdown	Total cumulative	% Breakdown of the total
	Current	of current	distributions for the	cumulative distributions
	distribution	distribution	fiscal year to date	for the fiscal year to date
Net Investment Income	0.00811	56%	0.04560	52%
Net Realized ST Cap Gains	0.00000	0%	0.00000	0%
Net Realized LT Cap Gains	0.00000	0%	0.00000	0%
Return of Capital or
Other Capital Source	0.00638	44%	0.04210	48%
Total (per common share)	0.01449	100%	0.08770	100%

Average annual total return (in relation to NAV) for the five years ended 4-30-2024	2.70%
Annualized current distribution rate expressed as a percentage of month end NAV as of 4-30-2024	9.55%
Cumulative total return (in relation to NAV) for the fiscal year through 4-30-2024	4.34%
Cumulative fiscal year distributions as a percentage of NAV as of 4-30-2024	4.82%

You should not draw any conclusions about the fund's investment performance from the amount of this distribution or from the terms of the fund's managed distribution plan.

The fund estimates that it has distributed more than its income and capital gains; therefore, a portion of your distribution may be a return of capital. A return of capital may occur, for example, when some or all of the money that you invested in the fund is paid back to you. A return of capital distribution does not necessarily reflect the fund's investment performance and should not be confused with "yield" or "income."

The amounts and sources of distributions reported in this notice are only estimates and are not being provided for tax-reporting purposes. The actual amounts and sources of the amounts for tax-reporting purposes will depend upon the fund's investment experience during the remainder of its fiscal year and may be subject to changes based on tax regulations. The fund will send you a Form 1099-DIV for the calendar year that will tell you how to report these distributions for federal income tax purposes. If you have any questions regarding this information, please call our fund service department at 1-800-637-2304 any business day from 9 a.m. to 5 p.m. Eastern time.

CIHSN-0524

MFS® Intermediate High Income Fund

P.O. Box 43078

Providence, RI 02940-3078

Notice to shareholders — Source of distribution

Distribution period	April-2024
Distribution amount per share	$0.01475

The following table sets forth the estimated amounts of the current distribution and the cumulative distributions paid this fiscal year to date from the following sources: net investment income, net realized short-term capital gains, net realized long-term capital gains and return of capital or other capital source. The fund’s fiscal year begins each December 1st. All amounts are expressed per common share.

		% Breakdown	Total cumulative	% Breakdown of the total
	Current	of current	distributions for the	cumulative distributions
	distribution	distribution	fiscal year to date	for the fiscal year to date
Net Investment Income	0.00752	51%	0.03661	50%
Net Realized ST Cap Gains	0.00000	0%	0.00000	0%
Net Realized LT Cap Gains	0.00000	0%	0.00000	0%
Return of Capital or
Other Capital Source	0.00723	49%	0.03660	50%
Total (per common share)	0.01475	100%	0.07321	100%

Average annual total return (in relation to NAV) for the five years ended 3-31-2024	3.48%
Annualized current distribution rate expressed as a percentage of month end NAV as of 3-31-2024	9.47%
Cumulative total return (in relation to NAV) for the fiscal year through 3-31-2024	6.28%
Cumulative fiscal year distributions as a percentage of NAV as of 3-31-2024	3.91%

You should not draw any conclusions about the fund's investment performance from the amount of this distribution or from the terms of the fund's managed distribution plan.

The fund estimates that it has distributed more than its income and capital gains; therefore, a portion of your distribution may be a return of capital. A return of capital may occur, for example, when some or all of the money that you invested in the fund is paid back to you. A return of capital distribution does not necessarily reflect the fund's investment performance and should not be confused with "yield" or "income."

The amounts and sources of distributions reported in this notice are only estimates and are not being provided for tax-reporting purposes. The actual amounts and sources of the amounts for tax-reporting purposes will depend upon the fund's investment experience during the remainder of its fiscal year and may be subject to changes based on tax regulations. The fund will send you a Form 1099-DIV for the calendar year that will tell you how to report these distributions for federal income tax purposes. If you have any questions regarding this information, please call our fund service department at 1-800-637-2304 any business day from 9 a.m. to 5 p.m. Eastern time.

CIHSN-0424

MFS® Intermediate High Income Fund

P.O. Box 43078

Providence, RI 02940-3078

Notice to shareholders — Source of distribution

Distribution period	March-2024
Distribution amount per share	$0.01476

The following table sets forth the estimated amounts of the current distribution and the cumulative distributions paid this fiscal year to date from the following sources: net investment income, net realized short-term capital gains, net realized long-term capital gains and return of capital or other capital source. The fund’s fiscal year begins each December 1st. All amounts are expressed per common share.

		% Breakdown	Total cumulative	% Breakdown of the total
	Current	of current	distributions for the	cumulative distributions
	distribution	distribution	fiscal year to date	for the fiscal year to date
Net Investment Income	0.00753	51%	0.02923	50%
Net Realized ST Cap Gains	0.00000	0%	0.00000	0%
Net Realized LT Cap Gains	0.00000	0%	0.00000	0%
Return of Capital or
Other Capital Source	0.00723	49%	0.02923	50%
Total (per common share)	0.01476	100%	0.05846	100%

Average annual total return (in relation to NAV) for the five years ended 2-29-2024	3.35%
Annualized current distribution rate expressed as a percentage of month end NAV as of 2-29-2024	9.52%
Cumulative total return (in relation to NAV) for the fiscal year through 2-29-2024	4.81%
Cumulative fiscal year distributions as a percentage of NAV as of 2-29-2024	3.14%

You should not draw any conclusions about the fund's investment performance from the amount of this distribution or from the terms of the fund's managed distribution plan.

The fund estimates that it has distributed more than its income and capital gains; therefore, a portion of your distribution may be a return of capital. A return of capital may occur, for example, when some or all of the money that you invested in the fund is paid back to you. A return of capital distribution does not necessarily reflect the fund's investment performance and should not be confused with "yield" or "income."

The amounts and sources of distributions reported in this notice are only estimates and are not being provided for tax-reporting purposes. The actual amounts and sources of the amounts for tax-reporting purposes will depend upon the fund's investment experience during the remainder of its fiscal year and may be subject to changes based on tax regulations. The fund will send you a Form 1099-DIV for the calendar year that will tell you how to report these distributions for federal income tax purposes. If you have any questions regarding this information, please call our fund service department at 1-800-637-2304 any business day from 9 a.m. to 5 p.m. Eastern time.

CIHSN-0324

MFS® Intermediate High Income Fund

P.O. Box 43078

Providence, RI 02940-3078

Notice to shareholders — Source of distribution

Distribution period	February-2024
Distribution amount per share	$0.01484

The following table sets forth the estimated amounts of the current distribution and the cumulative distributions paid this fiscal year to date from the following sources: net investment income, net realized short-term capital gains, net realized long-term capital gains and return of capital or other capital source. The fund’s fiscal year begins each December 1st. All amounts are expressed per common share.

		% Breakdown	Total cumulative	% Breakdown of the total
	Current	of current	distributions for the	cumulative distributions
	distribution	distribution	fiscal year to date	for the fiscal year to date
Net Investment Income	0.00831	56%	0.02185	50%
Net Realized ST Cap Gains	0.00000	0%	0.00000	0%
Net Realized LT Cap Gains	0.00000	0%	0.00000	0%
Return of Capital or
Other Capital Source	0.00653	44%	0.02185	50%
Total (per common share)	0.01484	100%	0.04370	100%

Average annual total return (in relation to NAV) for the five years ended 1-31-2024	3.81%
Annualized current distribution rate expressed as a percentage of month end NAV as of 1-31-2024	9.47%
Cumulative total return (in relation to NAV) for the fiscal year through 1-31-2024	5.70%
Cumulative fiscal year distributions as a percentage of NAV as of 1-31-2024	2.32%

You should not draw any conclusions about the fund's investment performance from the amount of this distribution or from the terms of the fund's managed distribution plan.

The fund estimates that it has distributed more than its income and capital gains; therefore, a portion of your distribution may be a return of capital. A return of capital may occur, for example, when some or all of the money that you invested in the fund is paid back to you. A return of capital distribution does not necessarily reflect the fund's investment performance and should not be confused with "yield" or "income."

The amounts and sources of distributions reported in this notice are only estimates and are not being provided for tax-reporting purposes. The actual amounts and sources of the amounts for tax-reporting purposes will depend upon the fund's investment experience during the remainder of its fiscal year and may be subject to changes based on tax regulations. The fund will send you a Form 1099-DIV for the calendar year that will tell you how to report these distributions for federal income tax purposes. If you have any questions regarding this information, please call our fund service department at 1-800-637-2304 any business day from 9 a.m. to 5 p.m. Eastern time.

CIHSN-0224

MFS® Intermediate High Income Fund

P.O. Box 43078

Providence, RI 02940-3078

Notice to shareholders — Source of distribution

Distribution period	January-2024
Distribution amount per share	$0.01475

The following table sets forth the estimated amounts of the current distribution and the cumulative distributions paid this fiscal year to date from the following sources: net investment income, net realized short-term capital gains, net realized long-term capital gains and return of capital or other capital source. The fund’s fiscal year begins each December 1st. All amounts are expressed per common share.

		% Breakdown	Total cumulative	% Breakdown of the total
	Current	of current	distributions for the	cumulative distributions
	distribution	distribution	fiscal year to date	for the fiscal year to date
Net Investment Income	0.00649	44%	0.01270	44%
Net Realized ST Cap Gains	0.00000	0%	0.00000	0%
Net Realized LT Cap Gains	0.00000	0%	0.00000	0%
Return of Capital or
Other Capital Source	0.00826	56%	0.01616	56%
Total (per common share)	0.01475	100%	0.02886	100%

Average annual total return (in relation to NAV) for the five years ended 12-31-2023	5.02%
Annualized current distribution rate expressed as a percentage of month end NAV as of 12-31-2023	9.37%
Cumulative total return (in relation to NAV) for the fiscal year through 12-31-2023	4.73%
Cumulative fiscal year distributions as a percentage of NAV as of 12-31-2023	1.53%

You should not draw any conclusions about the fund's investment performance from the amount of this distribution or from the terms of the fund's managed distribution plan.

The fund estimates that it has distributed more than its income and capital gains; therefore, a portion of your distribution may be a return of capital. A return of capital may occur, for example, when some or all of the money that you invested in the fund is paid back to you. A return of capital distribution does not necessarily reflect the fund's investment performance and should not be confused with "yield" or "income."

The amounts and sources of distributions reported in this notice are only estimates and are not being provided for tax-reporting purposes. The actual amounts and sources of the amounts for tax-reporting purposes will depend upon the fund's investment experience during the remainder of its fiscal year and may be subject to changes based on tax regulations. The fund will send you a Form 1099-DIV for the calendar year that will tell you how to report these distributions for federal income tax purposes. If you have any questions regarding this information, please call our fund service department at 1-800-637-2304 any business day from 9 a.m. to 5 p.m. Eastern time.

CIHSN-0124

MFS® Intermediate High Income Fund

P.O. Box 43078

Providence, RI 02940-3078

Notice to shareholders — Source of distribution

Distribution period	December-2023
Distribution amount per share	$0.01411

The following table sets forth the estimated amounts of the current distribution and the cumulative distributions paid this fiscal year to date from the following sources: net investment income, net realized short-term capital gains, net realized long-term capital gains and return of capital or other capital source. The fund’s fiscal year begins each December 1st. All amounts are expressed per common share.

		% Breakdown	Total cumulative	% Breakdown of the total
	Current	of current	distributions for the	cumulative distributions
	distribution	distribution	fiscal year to date	for the fiscal year to date
Net Investment Income	0.01411	100%	0.01411	100%
Net Realized ST Cap Gains	0.00000	0%	0.00000	0%
Net Realized LT Cap Gains	0.00000	0%	0.00000	0%
Return of Capital or
Other Capital Source	0.00000	0%	0.00000	0%
Total (per common share)	0.01411	100%	0.01411	100%

Average annual total return (in relation to NAV) for the five years ended 11-30-2023	3.56%
Annualized current distribution rate expressed as a percentage of month end NAV as of 11-30-2023	9.30%
Cumulative total return (in relation to NAV) for the fiscal year through 11-30-2023	10.13%
Cumulative fiscal year distributions as a percentage of NAV as of 11-30-2023	0.78%

You should not draw any conclusions about the fund's investment performance from the amount of this distribution or from the terms of the fund's managed distribution plan.

The fund estimates that it has distributed more than its income and capital gains; therefore, a portion of your distribution may be a return of capital. A return of capital may occur, for example, when some or all of the money that you invested in the fund is paid back to you. A return of capital distribution does not necessarily reflect the fund's investment performance and should not be confused with "yield" or "income."

The amounts and sources of distributions reported in this notice are only estimates and are not being provided for tax-reporting purposes. The actual amounts and sources of the amounts for tax-reporting purposes will depend upon the fund's investment experience during the remainder of its fiscal year and may be subject to changes based on tax regulations. The fund will send you a Form 1099-DIV for the calendar year that will tell you how to report these distributions for federal income tax purposes. If you have any questions regarding this information, please call our fund service department at 1-800-637-2304 any business day from 9 a.m. to 5 p.m. Eastern time.

CIHSN-1223